US 7279584

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Search Results Summary

Important caveat on the searches: My web searches did not return any authoritative USPTO records or any CAFC 2026 docket activity matching US7279584. The results returned were unrelated (e.g., a Japanese Patent No. JP7279584B2 belonging to Daifuku Co. — "物品収納設備"/article storage equipment — which is a different patent with a coincidentally similar number; and unrelated PCT search reports). I did not locate any litigation, appeal, or PTAB proceeding involving US7279584. I have no authoritative information on CAFC 2026 dockets for this patent, and I will not speculate. The summary below is grounded in the authoritative full patent text provided in your message.

US Patent 7,279,584 — Concise Summary

Abstract

The invention provides a safer method for producing a cis-4-fluoro-L-proline derivative under milder conditions, in good yield and high purity, on an industrial scale and at low cost. Specifically, a trans-4-hydroxy-L-proline derivative of Formula [I] (wherein R¹ is an α-amino protecting group and R² is a carboxyl protecting group) is reacted with N,N-diethyl-N-(1,1,2,3,3,3-hexafluoropropyl)amine ("Ishikawa reagent") in the presence of a hydrogen fluoride-scavenger.

Plain-Language Overview of the Claims

The patent has 7 claims total, with only one independent claim (claim 1). Claims 2–7 are dependent.

Claim 1 (the only independent claim) — the core method:
A two-step-reagent process for making a cis-4-fluoro-L-proline derivative (Formula [II]). You take a trans-4-hydroxy-L-proline derivative (Formula [I]), where R¹ is any α-amino protecting group and R² is any carboxyl protecting group, and react it with N,N-diethyl-N-(1,1,2,3,3,3-hexafluoropropyl)amine (the Ishikawa reagent) in the presence of (a) a hydrogen fluoride-scavenger and (b) a reaction solvent. This converts the 4-position hydroxyl into a fluorine, giving the cis-fluoro product. The key inventive point is the HF-scavenger, which traps the hydrogen fluoride byproduct that otherwise corrodes vessels and decomposes starting materials/products — especially acid-labile urethane protecting groups (e.g., Boc).

Claim 2 (depends on 1): Narrows the permissible protecting groups:

• R¹ (α-amino): an aromatic urethane, aliphatic urethane, cycloalkylurethane, acyl, sulfonyl, or alkyl-type protecting group.
• R² (carboxyl): a C₁–C₄ alkyl group optionally substituted with halogen(s), or a benzyl, allyl, phenacyl, or benzhydryl group optionally substituted with C₁–C₄ alkoxy, C₁–C₄ alkyl, nitro, or halogen substituents.

Claim 3 (depends on 1): Further narrows to specific named groups:

• R¹: benzyloxycarbonyl (Z), tert-butoxycarbonyl (Boc), 4-methoxybenzyloxycarbonyl, 9-fluorenylmethyloxycarbonyl (Fmoc), allyloxycarbonyl, formyl, acetyl, phthaloyl, or trityl.
• R²: methyl, ethyl, tert-butyl, benzyl, 4-methoxybenzyl, 4-nitrobenzyl, allyl, phenacyl, trichloroethyl, or benzhydryl.

Claim 4 (depends on any of 1–3): Specifies that the hydrogen fluoride-scavenger is an alkali metal salt of fluorine (e.g., NaF, KF, CsF, RbF).

Claim 5 (depends on 4): Specifies the scavenger is specifically sodium fluoride (NaF).

Claim 6 (depends on any of 1–3): Specifies the reaction solvent is an inert solvent (e.g., halogenated solvents like dichloromethane, chloroform, 1,2-dichloroethane; hydrocarbon solvents; esters; acetonitrile).

Claim 7 (depends on 6): Specifies the solvent is dichloromethane.

Practical Significance (from the specification)

• Comparative data show the HF-scavenger's effect is dramatic: with Ishikawa reagent alone (1.9 eq, 12 °C, 20 h), yield was only 14%; adding NaF raised yield to 85% at the same conditions, and 85% again with only 1.2 eq of reagent at 21 °C in 8 h.
• The examples describe fluorination of N-Boc- and N-Cbz-protected methyl trans-4-hydroxyproline esters, and a reference example traces the product onward to the DPP-IV inhibitor (2S,4S)-4-fluoro-1-{[(2-hydroxy-1,1-dimethylethyl)amino]acetyl}pyrrolidine-2-carbonitrile monobenzenesulfonate.
• The cited prior art includes Giardina et al., Synlett (1995) and Demange et al., Tetrahedron Lett. 39, 1169 (1998) (DAST-based fluorination).

Uncertainty Notes

• Patent number interpretation: Per your strict rule, US7279584 = US 7,279,584. I did not auto-correct or reassign it. Note that "JP7279584" appearing in search results is a distinct Japanese patent (Daifuku) and was not treated as related.
• CAFC 2026 dockets: No CAFC 2026 docket entry, appeal, or litigation involving US7279584 was found in my searches. I cannot confirm any such activity exists; absence of search results is not proof of absence.
• The expiration/lapse dates and "Expired – Fee Related" status come from the provided Google Patents record; the record itself notes legal status is an assumption, not a legal conclusion.

I'll search for litigation involving US patent 7279584 across patent litigation resources.

Initial searches returned unrelated results. Let me search more targeted patent litigation databases.

Let me search dedicated litigation trackers and court records directly.

Summary of Findings

I searched for litigation involving US Patent 7,279,584 ("Method for production of cis-4-fluoro-L-proline derivatives," Taisho Pharmaceutical Co., Ltd.) across patent litigation resources, but I was unable to identify any litigation — district court, CAFC, ITC, or PTAB — involving this specific patent, and no litigation is listed on the patent's public record.

What I checked

• General web searches for the patent number combined with "litigation," "infringement," "lawsuit," and "complaint."
• Searches keyed to the assignee (Taisho Pharmaceutical) and the technology (cis-4-fluoro-L-proline / DPP-IV / fluoroproline intermediates).
• The Google Patents record supplied in the authoritative text, which includes "Cited By," citation, and family data but no litigation section and no PTAB/reexamination proceedings.

Negative results — and important traps to avoid

Two near-number matches appeared but are not this patent; I flag them so they are not mistakenly attributed:

1. US Patent 5,965,584 ("the '584 Patent") — the Takeda ACTOS/pioglitazone litigation (e.g., Takeda Pharm. Co. v. Teva Pharm. Indus., No. 09-cv-4665 (S.D.N.Y.)). This is a different patent (5,965,584 ≠ 7,279,584) and different technology.
2. JP 7279584 B2 — a 2023 Japanese patent (No. 7279584) assigned to Daifuku Co., Ltd. for a warehouse storage system. This shares only the numeric string; it is not the US patent and not related.

No US case, jurisdiction, case number, or filing date involving 7,279,584 surfaced in my searches.

Patent status context (from the authoritative record)

• Patent: US 7,279,584 B2
• Assignee: Taisho Pharmaceutical Co., Ltd.
• Priority date: 2003-08-18 (JP 2003-207718); filed: 2004-08-18 (PCT/JP2004/011827); granted: 2007-10-09
• Legal status: Expired – Fee Related. The maintenance fee was not paid; the patent lapsed effective 2011-10-09 (lapse notice 2011-10-09; discontinued 2011-11-07).
• Related family: EP 1657237 A1 (withdrawn), WO 2005016880 A1 (ceased), KR 20060037417 A (withdrawn), JP WO2005016880 (withdrawn), AU 2004265182 A1 (abandoned), CA 2534884 A1 (abandoned), CN 1839120 A (pending/active), among others.

Caveats

I was limited to the searches I could run and did not directly query PACER, Docket Navigator, or the Unified Patents litigation portal case lists. My searches returned no evidence of litigation, but I cannot certify a definitive negative for the entire life of the patent. If you need an exhaustive affirmative clearance, I recommend a targeted Docket Navigator / Lex Machina / PACER party-and-patent search, plus a check of the patent's USPTO PatentCenter "Proceedings" tab and the EP/CN/JP counterpart dockets — but based on all available information, and consistent with the patent having been allowed to lapse in 2011, no litigation is known to have involved US 7,279,584.

If you'd like, I can run further targeted queries (e.g., a specific PACER/docket search string for "7,279,584 Taisho") once additional search steps are available.

Proceedings overview

Zero AIA trial proceedings on file. The USPTO Open Data Portal (ODP) structured block returns no IPR, PGR, or CBM proceedings involving US 7,279,584 B2, and my supplemental web searches surfaced no proceeding numbers, decisions, or Federal Circuit appeals tied to this patent — so the count is 0 active / 0 claims invalidated / 0 claims sustained / 0 settled / 0 institution denials. The defensive posture for a defendant is therefore not "hardened patent" (there is no PTAB precedent validating or invalidating anything) and not "claims canceled by the Board." It is something more basic: no claims of this patent have ever been tested at the PTAB — and, critically, none could have been tested during the patent's enforceable life, because the patent lapsed for nonpayment of maintenance fees on 2011-10-09, roughly eleven months before the first IPR was even filed in the United States (IPR became available under the AIA on 2012-09-16).

No proceedings to enumerate

Because the canonical list is empty and no proceeding was found in search, there are no ### {PROCEEDING_NUMBER} — {Petitioner} v. {Patent Owner} sections to populate. I will not manufacture proceeding numbers, panels, or dispositions to fill the template. What follows explains why the list is empty and what that means.

Procedural availability analysis (this is the real finding):

The Board may institute IPR on an expired patent, so the absence of an IPR is not literally a legal impossibility — but no challenger ever filed one, which is unsurprising for a patent that had already lapsed and whose assignee (Taisho) never asserted it in the litigation I was able to find (consistent with the previously generated litigation summary, which likewise found no suits).

Searches run and what they returned (all negative for this patent):

• "7,279,584" IPR PTAB inter partes review → unrelated proceedings (Intellectual Ventures, Samsung, etc.)
• "7279584" patent PTAB trial proceeding Taisho → the unrelated JP 7279584 B2 (Daifuku, "物品収納設備") again, plus the FreePatentsOnline copy of the US patent
• PTAB IPR2023/IPR2024/IPR2025 "Taisho Pharmaceutical" fluoroproline inter partes review → unrelated
• "7,279,584" OR "7279584" Federal Circuit appeal → unrelated dockets (a Seventh Circuit tax case docket number and an unrelated Fed. Cir. notice, 2026-2012, Contour IP v. GoPro)

⚠️ Trap to avoid (carried forward): the string "7279584" repeatedly appears as a docket-entry number (e.g., [7279584] in a Seventh Circuit filing) and as a Japanese patent number (JP 7279584 B2, Daifuku). Neither is US 7,279,584, and neither is a PTAB proceeding. Search engines conflate all three; I did not attribute any of them to this patent.

Strategic summary

Claim status: every claim is untested and unadjudicated — but also unenforceable as of 2011-10-09. Claims 1–7 exist on paper exactly as issued on 2007-10-09: claim 1 (independent, the Ishikawa-reagent/HF-scavenger fluorination method), claims 2–3 (protecting-group narrowing), claim 4 (alkali metal fluoride scavenger), claim 5 (NaF), claim 6 (inert solvent), claim 7 (dichloromethane). None were canceled, narrowed by amendment, or held unpatentable in any post-grant proceeding, because no post-grant proceeding was ever filed. Contrast this with the ordinary "asserted patent" pattern: the enforcement data shows the patent was allowed to lapse for failure to pay the maintenance fee due around 2011-10-09, and it carried "Expired – Fee Related" status thereafter. An expired patent cannot be infringed going forward, and any retrospective royalty claim is subject to the 35 U.S.C. § 286 six-year damages bar — a window that closed roughly fifteen years ago. That, not any PTAB outcome, is the dispositive fact for a defendant.

Estoppel landscape: there is none, and none is needed. Because no IPR/PGR/CBM was ever instituted and no Final Written Decision ever issued, no petitioner is bound by § 315(e)(1)/(2) or § 325(e)(1)/(2) estoppel on this patent. Conversely, the patent owner has no adverse PTAB record to appeal — no § 141(c) / § 319 Federal Circuit appeal exists, and I found none on the Federal Circuit docket or CourtListener. There is no defensive aggregator (Unified Patents, RPX, etc.) in the chain; the patent's "Cited By" and "Families Citing" data show only ordinary prosecution and follow-on chemistry art (e.g., Ube's US 8,203,003; WO2006103986 to Tosoh F-Tech on optically active fluoroproline derivatives).

Pattern signals: none — the file is dormant. There is only one family member in the US (application 10/568,708, now the '584 patent), the foreign counterparts are uniformly dead or stalled (EP 1657237 A1 withdrawn; WO 2005016880 ceased; KR 20060037417 A withdrawn; JP, AU, CA, NO abandoned/discontinued; only CN 1839120 A listed as pending/active in the record), and the last substantive legal event was the 2011-11-29 lapse. No petitioner filed more than one petition; no patent owner pursued any PTAB appeal, because there were no PTAB proceedings. Anyone receiving a demand letter on this patent today should treat the letter itself — not the patent — as the anomaly worth scrutinizing.

Recommended next steps

1. If you are a defendant / recipient of a demand letter: The patent is expired. Per the record, the maintenance fee lapse was noticed 2011-10-09, status was changed to "patent discontinued" on 2011-11-07, and the formal lapse ("PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362") was recorded 2011-11-29. There is no Final Written Decision to link to or quote, because no FWD exists — say so plainly rather than pointing to a nonexistent opinion. Confirm current status at the USPTO PatentCenter "Maintenance Fees"/"Proceedings" tabs (https://patentcenter.uspto.gov) and on the PTAB's public portals before responding.
2. Verification sources for the "no PTAB activity" conclusion: USPTO Patent Trial and Appeal Board End-to-End (PTAB E2E) proceeding search and the PTAB Decisions portal at https://www.uspto.gov/patents/ptab/decisions, plus the USPTO Open Data Portal API (the canonical source for this task's structured block). For any appeal, check the Federal Circuit docket and CourtListener, https://www.courtlistener.com. I ran these indirectly through search only; I did not directly query PTAB E2E.
3. Because there are no active proceedings, there are no trial-stage milestones to calendar — no institution-decision deadline, no oral hearing, no statutory one-year FWD due date under 35 U.S.C. § 316(a)(11). Anyone telling you a PTAB trial is pending on 7,279,584 is either describing a different patent or mistaken.
4. Do not mis-attribute the lookalikes. Keep three distinct things separate: (a) US 7,279,584 (Taisho, expired 2011); (b) US 5,965,584 (Takeda, pioglitazone litigation — different patent, different number); and (c) JP 7279584 B2 (Daifuku, article-storage equipment — different country, different technology). The absence of PTAB activity here is a real signal (dormant, lapsed patent), but it is amplified by search-engine noise that fabricates apparent activity on this number.

Explicit confidence statement: I am highly confident the PTAB proceedings list for US 7,279,584 is empty — grounded in the canonical ODP-derived block stating no AIA trial proceedings, corroborated by negative search results and by the fact that the patent lapsed before IPR existed. I did not directly query PTAB E2E, Docket Navigator, Lex Machina, or PACER, so I cannot certify a negative from primary sources; the structured block is the controlling evidence. If a proceeding number surfaces later that the ODP ingest missed, flag it and I will re-run the claim-level outcome analysis against the FWD.

I'll research the assignment record for US7279584 across the sources specified.

Assignment Record Reconstruction — US 7279584 (US 7,279,584 B2)

Important sourcing caveat up front: I was unable to reach assignmentcenter.uspto.gov or the legacy assignment.uspto.gov index directly in this session (my queries returned generic explainer pages about the USPTO's 2024 Assignment Center rollout, not the record itself). The assignment data below therefore comes from the Google Patents legal-events record embedded in the authoritative patent text, which mirrors the USPTO assignment index (it reports the same reel/frame). I could confirm one recorded assignment; I could not retrieve the corresponding correspondent of record — that field is absent from the provided record and would need a direct Assignment Center query (search by patent number 7,279,584, or by app. 10/568,708) to capture. I have not fabricated a correspondent name.

Inventors

Four inventors are named on the face of the patent:

Basis for the employer inference: The single recorded assignment (reel 019545/0229) lists all four as assignors conveying rights to Taisho Pharmaceutical Co., Ltd., and the PCT/CN family records (e.g., CN-1839120-A) likewise list Taisho as applicant/assignee with these inventors. This is consistent with an in-house R&D team, not independent inventors.

Pattern notes:

• No unusual departure pattern determinable. The assignment was executed 2006-06-23 (effective date), recorded 2006-08-04 — roughly 22 months after the 2004-08-18 PCT filing and nearly 3 years after the 2003-08-18 JP priority. That is a routine confirmatory inventor-to-company assignment taken for the U.S. national-stage entry, not the sub-12-month mass-departure signature the task flags. I have no evidence that any inventor left Taisho.
• The movers matched the previously generated sections; consistent.

Original assignee

Taisho Pharmaceutical Co., Ltd. (Japan) — named as both Original Assignee and Current Assignee on the patent record.

• Primary line of business: Research-based pharmaceutical manufacturer (prescription and OTC medicines), headquartered in Tokyo, Japan. Consumer-health and prescription segments.
• Product embodying the claims: The claims are to a method of manufacture of a cis-4-fluoro-L-proline synthetic intermediate — there is no end product per se. The specification's Reference Example traces the intermediate onward to the DPP-IV inhibitor (2S,4S)-4-fluoro-1-{[(2-hydroxy-1,1-dimethylethyl)amino]acetyl}pyrrolidine-2-carbonitrile monobenzenesulfonate (a cyanopyrrolidine anti-diabetic candidate). So the "product" is an internal process for making a pharma intermediate, not a commercial article of commerce sold under the claims.
• Current status: Operating company; the patent record itself lists Taisho as current assignee. I could not independently verify Taisho's 2026 corporate status (M&A, restructuring) within this session — no search results on that point were retained — so I flag that as unverified rather than assert a change.
• Key status fact from the record: The patent was allowed to lapse for non-payment of maintenance fees, effective 2011-10-09 (lapse notice 2011-10-09; discontinuation recorded 2011-11-07; expiration event 2011-11-29). A company that abandons its own process patent within ~4 years of issue is not behaving like an assertion vehicle.

Assignment timeline

One (1) recorded assignment exists. No security agreements, mergers, changes of name, licenses, releases, or corrections appear in the legal-events record.

• 2006-06-23 (executed) / recorded 2006-08-04 — Reel 019545/0229
  • Conveyance: Assignment — recorded under code AS, free-format text "ASSIGNMENT OF ASSIGNORS INTEREST"
  • Assignor: Tomisawa, Kazuyuki; Tatsuta, Dai; Yoshida, Tomomichi; and Others (the "Others" = Chihiro Yokoo, the fourth named inventor)
  • Assignee: Taisho Pharmaceutical Co., Ltd., Japan
  • Correspondent: Not stated in the provided record. No attorney/agent of record was captured; a direct Assignment Center lookup is required to obtain this field. (No recurrence to flag — with only one assignment there is no chain on which a correspondent could repeat.)
  • Context: Internal — inventor-to-company confirmatory assignment of rights to the original assignee, executed ~22 months after filing to support the U.S. national-stage entry. Not a sale, fire-sale, or transfer-to-asserter.

Plain statement: The Assignment Center (as reflected in the mirrored legal-events data) contains no post-issuance assignment for this patent. The original assignee Taisho Pharmaceutical Co., Ltd. remained the owner from the inventor assignment through lapse. That is itself the finding — it is the classic profile of an operating company that kept its own process patent, never moved it to an NPE vehicle, and let it expire.

Timeline diagram

timeline
    title Ownership of US 7279584
    2003 : Priority application filed in Japan
    2004 : PCT application filed
    2006 : Inventors assign rights to Taisho
         : Reel 019545 frame 0229
    2007 : US patent issued
    2011 : Patent lapsed for unpaid fees

NPE / troll-pattern signals

Verdict

Insufficient data (per the defined category "no records, or only the original assignment") — with the substantive finding that no NPE pattern exists.

The ownership chain consists of exactly one recorded assignment — reel 019545/0229, executed 2006-06-23 and recorded 2006-08-04 — conveying rights from the four named inventors to Taisho Pharmaceutical Co., Ltd. There are no subsequent assignments, no shell-entity transferee, no known asserter, no cascading transfers, and no pre-litigation transfer. The patent remained with its original operating-company assignee and lapsed for non-payment of maintenance fees effective 2011-10-09 (discontinuation 2011-11-07). On the definitional thresholds, this is not an NPE/troll chain on any signal — it is an unremarketed process patent that a pharma company let die.

Caveats and next steps for verification:

• I could not open https://assignmentcenter.uspto.gov/ directly; the reel/frame above is taken from the mirrored Google Patents legal-events record. To confirm and to capture the correspondent of record, query the Assignment Center by patent number 7,279,584 or application 10/568,708.
• I also could not retrieve Taisho's current corporate status (M&A/restructuring) in this session; treat the "operating" call as based on the record, not an independent 2026 corporate check.
• Consistent with the constraints: I have not fabricated any assignment, correspondent, or reel/frame. The only reel/frame asserted is the one documented in the source text.

Verification link: USPTO Assignment Center — https://assignmentcenter.uspto.gov/ (search patent number 7279584)

I'll search for the specific patent and its citations. Let me run several targeted queries.

Let me gather more detail on the cited references and verify the front-page citation list.

Prior Art Analysis — US Patent 7,279,584 (Application 10/568,708)

Tool-budget note / provenance caveat: I spent the available search steps and could not open a live USPTO Patent Public Search / PatentCenter page directly. The front-page citation data below is taken from the authoritative full-text record supplied in your message (the Google Patents rendering of the USPTO front page for US 7,279,584), cross-checked where possible against my search hits. Google's citation list generally mirrors the examiner-cited "References Cited" on the USPTO front page, but it is not guaranteed to be exhaustive of every reference cited during prosecution (particularly those raised only in the JP/KR/CN/EP family members).

1. Confirmation of the record searched

Because the application was filed in 2004, pre-AIA 35 U.S.C. § 102 governs. Anticipation under § 102 requires a single reference disclosing every element of the claim, arranged as in the claim (In re Paulsen; MPEP 2131). For claim 1, that means a single reference must disclose reacting a trans-4-hydroxy-L-proline derivative (Formula [I]) with N,N-diethyl-N-(1,1,2,3,3,3-hexafluoropropyl)amine (Ishikawa reagent) in the presence of an HF-scavenger and a reaction solvent.

2. References cited on the face of US 7,279,584

2a. Patent citations (3)

① US 6,384,234 B1

• Full citation: US 6,384,234 B1, "N-arylsulfonamide- and pyrrolidinecarboxylic acid intermediates, and their use for the preparation of herbicidal 1,3-dioxo-1H-pyrrolo[1,2-c]imidazole derivatives." Assignee: Degussa AG (co-work with DuPont; inventors incl. E. D. Taylor, V. A. Petrov, M. Schaeffer, et al.). Family: CN 98802692 / WO 98/~ (published as US 2002/0137946 A1 and US 6,664,400 B2 family).
• Dates: Priority 1997-02-19; granted 2002-05-07.
• Brief description: Discloses intermediates of Formulae (3) and (6) — substituted pyrrolidine-2-carboxylic acid derivatives bearing H/OH (R³) and H/F/Cl (R⁴) at the ring positions — and processes for making them (halogenation, cyclization, sulfonylation, hydrolysis) en route to herbicidal sulfonamides. It is a herbicide-intermediate patent, not a fluorination-methodology patent.
• § 102 relevance: None (no anticipation). It is directed to different compounds and process steps. It does not disclose the Ishikawa reagent, and does not disclose fluorinating the 4-OH of a trans-4-hydroxy-L-proline derivative in the presence of an HF-scavenger. It touches the subject matter of dependent claims 2/3 only tangentially (pyrrolidinecarboxylate intermediates that may carry F and protecting/ester groups), but a § 102 anticipation argument would fail because it does not teach the claim-1 reaction.

② JP 2002-275267 A

• Full citation: JP 2002-275267 A, "Ligand compound immobilized in polymer, its catalyst and method for asymmetric conjugate addition reaction of thiols." Applicant: Japan Science & Technology Corp. (Japan Science and Technology Agency); inventor Osamu Kobayashi.
• Dates: JP application JP2001075090A; priority 2001-03-15; published 2002-09-25.
• Brief description: Polymer-supported proline-derived ligands and their use (with Hf(OTf)₄) as chiral catalysts for the Michael-type conjugate addition of thiols to α,β-unsaturated carbonyls. It concerns asymmetric catalysis/ligand immobilization.
• § 102 relevance: None (no anticipation). No fluorination chemistry; no Ishikawa reagent; no HF scavenger. It is cited only because it discloses proline derivatives generically. Not anticipatory of any of claims 1–7.

③ JP 2006-103986 A

• Full citation: JP 2006-103986 A, "Cement-based surface covering material." Applicant: Taiheiyo Material K.K.
• Dates: Priority 2004-09-30; published 2006-04-20.
• Brief description: A cementitious surface-coating material — entirely unrelated to proline or fluorine chemistry.
• § 102 relevance: None — and it is not prior art at all. Its priority date (2004-09-30) and publication date (2006-04-20) post-date the 2003-08-18 priority date of US 7,279,584. A reference that postdates the priority date cannot anticipate under pre-AIA § 102(a) or (b) (and a foreign publication is not § 102(e) art).
• ⚠️ Flag for the file: This entry is almost certainly a data artifact in the machine-generated citation list (the same JP number also appears with a 2004-09-30 priority in the "Citations" block). It has no technical relationship to the patent and should not be treated as substantive prior art. I did not auto-correct or substitute another number; I describe it literally as listed.

2b. Non-patent citations (2)

④ G. Giardina, G. Dondio, M. Grugni, Synlett 1995, No. 1, pp. 55–57

• Full citation: "Facile and Efficient Syntheses of Novel (S)- and (R)-3-Fluoropyrrolidines and 3,3-Difluoropyrrolidine," Synlett 1995, (1), 55–57; DOI 10.1055/s-1995-4862 (SmithKline Beecham Farmaceutici, Milan).
• Date: 1995 (Synlett issue No. 1, 1995).
• Brief description: Starts from enantiomerically pure (2S,4R)-4-hydroxyproline; introduces fluorine by (i) tosylate displacement with spray-dried KF and (ii) DAST for difluorination — yielding 3-fluoro- and 3,3-difluoropyrrolidines (κ-opioid-agonist targets). Notably makes 3-fluoro, not 4-fluoro, products.
• § 102 relevance: None (no anticipation). It uses DAST and KF-mediated tosylate displacement — not the Ishikawa reagent — and does not disclose an HF-scavenger used together with a fluoroalkylamine reagent. It is genuine background art for the specification's discussion of DAST, but it does not disclose the claim-1 combination. (It discloses KF, an alkali-metal fluoride used as a fluoride nucleophile — not as an HF scavenger) — not anticipatory of claim 4 or 5.

⑤ L. Demange, A. Ménez, C. Dugave, Tetrahedron Letters 1998, 39(10), 1169–1172 ← most relevant prior art

• Full citation: "Practical synthesis of Boc and Fmoc protected 4-fluoro and 4-difluoroprolines from trans-4-hydroxyproline," Tetrahedron Lett. 1998, 39(10), 1169–1172; DOI 10.1016/S0040-4039(97)10793-6 (CEA/Saclay, France).
• Date: Submitted 1997-10-22; accepted 1997-12-06; published 5 March 1998.
• Brief description: Synthesizes Boc- and Fmoc-protected cis-4-fluoro-L-proline (71%, 3 steps) and 4-difluoro-L-proline (65%) from trans-4-hydroxy-L-proline methyl ester, using DAST for the fluorination; the cis/trans-4-fluoro-trans-isomer (24%) and Fmoc analogues are also made. It reports the DAST route giving 81% for cis-4-fluoroproline (the figure the specification itself repeats).
• § 102 relevance: Closest art, but no anticipation of any claim. It discloses the same product class (cis-4-fluoro-L-proline esters/protected derivatives; substituents recited in dependent claims 2/3 such as Boc, Fmoc, methyl ester) — but it uses DAST, not N,N-diethyl-N-(1,1,2,3,3,3-hexafluoropropyl)amine, and discloses no HF-scavenger. It therefore fails the all-elements test for claim 1 and, a fortiori, for all dependent claims. It is best characterized as § 103 (obviousness) art, not § 102 art.

3. § 102 anticipation conclusion

No reference cited on the face of US 7,279,584 anticipates any of claims 1–7. The reason is structural: every claim depends from claim 1, and claim 1's novelty/non-obviousness resides in the specific reagent/auxiliary combination — (a) the Ishikawa reagent and (b) an HF-scavenger, in a reaction solvent — applied to the trans-4-hydroxy-L-proline substrate. That combination appears in none of the cited references:

• Claim 1: Not anticipated by any cited reference.
• Claims 2–3 (protecting groups): Not anticipated (each depends on claim 1's unreached reaction). Demange and US 6,384,234 overlap some recited group members (Boc, Fmoc, methyl ester) but do not disclose the claimed process.
• Claim 4 (alkali metal fluoride scavenger) / Claim 5 (NaF): Not anticipated. Giardina uses KF as a nucleophilic fluoride source (tosylate displacement), which is a different role from the claimed hydrogen fluoride-scavenger; it does not disclose the claimed combination, and no reference discloses NaF as an HF scavenger with Ishikawa reagent.
• Claims 6–7 (inert solvent / dichloromethane): Not anticipated (dependent on claim 1).

Practical takeaway: Demange et al. (1998) is the most relevant reference to preserve for an invalidity analysis — but it supports an obviousness challenge (e.g., "modify DAST fluorination or substitute the fluorinating agent; add a fluoride scavenger") rather than a § 102 anticipation attack, and it must overcome the patent's own comparative evidence that the HF-scavenger changes the yield from 14% (Ishikawa alone) to 85% (with NaF).

4. Explicit uncertainties

• I could not run a live USPTO PatentCenter / Patent Public Search query or open the examiner's full "References Cited" list within the tool budget; the citation set above is from the authoritative record in your message (Google Patents rendering of the USPTO front page).
• The JP 2006-103986 A entry is technically incoherent as prior art (postdates the priority date; unrelated subject matter) and appears to be a listing artifact — reported literally, not corrected.
• Google Patents citation lists may omit references cited only in foreign family members (e.g., the CN 1839120 A or EP 1657237 A1 prosecution). An exhaustive § 102 clearance should retrieve those national-phase search reports directly.
• I have no basis to state that any non-cited reference anticipates the claims; I did not identify one, and absence of evidence is not proof of absence.

I'll ground this analysis by checking a few key references and general-knowledge points before writing.

Obviousness Analysis — US 7,279,584 B2 under 35 U.S.C. § 103

Analyst note on scope and date. This is a technical/analytical assessment, not a legal opinion. The patent has an effective priority date of 2003-08-18 and a US/international filing date of 2004-08-18, so the governing provision is pre-AIA 35 U.S.C. § 103(a). Prior art is measured against the 2003-08-18 critical date. I have built this on the previously generated sections (summary, claim breakdown, litigation findings) and do not repeat them. Where a reference listed on the page is not citable prior art, I flag it.

I use the prior-art materials listed on the Google Patents record (Patent Citations ×3; Non-Patent Citations ×2), plus the admissions in the '584 specification and general knowledge of the field confirmed by search, as permitted under the "scope and content of the prior art" inquiry of Graham v. John Deere Co., 383 U.S. 1 (1966), and KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007).

1. Legal standard applied

Under § 103(a), the claim is unpatentable if "the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art." The four Graham factors: (1) scope/content of the prior art; (2) differences between the prior art and the claims; (3) level of ordinary skill; (4) secondary considerations (objective indicia). Under KSR, a combination is obvious where the prior art elements are known and the combination was "obvious to try" — e.g., a "known technique" used to improve similar methods, "simple substitution of one known element for another," or "a finite number of identified, predictable solutions" — and where there was a "reasonable expectation of success." In re Keller, 642 F.2d 413 (CCPA 1981) (combining references; a reference need not address the very problem the applicant addressed).

2. Person of ordinary skill in the art (PHOSITA)

A synthetic/process organic chemist (advanced degree or equivalent) with several years' experience in fluorination chemistry and amino-acid/proline intermediates, familiar with the standard arsenal of dehydroxyfluorinating reagents (DAST, Deoxo-Fluor, Ishikawa/Yarovenko reagents) and with industrial handling of HF byproducts. This is a mature, well-populated art.

3. Scope and content of the prior art

Supplemental general knowledge (confirmed by search, all pre-2003):

• Ishikawa reagent = N,N-diethyl-1,1,2,3,3,3-hexafluoropropanamine (Takaoka, Iwakiri & Ishikawa, Bull. Chem. Soc. Jpn. 52(11), 3377 (1979)) is a long-known, shelf-stable, inexpensive dehydroxyfluorinating agent that converts alcohols to fluorides; it is expressly "a popular alternative to the DAST reagent" because it is shelf-stable and cheaply made (Wikipedia/Ishikawa reagent; Thieme Science of Synthesis "Organo-Fluorine Compounds").
• NaF scavenges HF: NaF + HF → NaHF₂ (sodium bifluoride) is textbook; NaF beds/traps are standard HF scrubbers (e.g., the ORNL/OSTI NaF HF-scrubber study; Exfluor US 4,859,747 teaches fluorinating in the presence of an HF scavenger — "sodium fluoride is the preferred… NaF will react with HF produced during fluorination to give sodium bifluoride (NaF + HF → NaHF₂) thus eliminating HF," and states the scavenger improves yield and quality and prevents the HF from reacting with the substrate).
• Handling of HF released by Yarovenko/Ishikawa-type reagents is a recognized scale-up problem (e.g., a thesis discussion: "the use of such reagents… small quantities of HF are released… In the perspective of industrial scale processes, the handling of HF will have to be dealt with… with specific care about released hydrofluoric acid").

Specification admissions (usable as evidence of the state of the art). The '584 background itself admits: (a) DAST gives the product in good yield but is "unsuitable for industrial use because DAST is highly toxic and less heat stable, as well as being explosive and expensive"; (b) the Ishikawa-reagent route on this substrate was known, and "there is a problem of reduced yield… because hydrogen fluoride generated during the reaction causes… erosion of reaction vessels, but also decomposition of starting materials and reaction products"; and (c) urethane protecting groups "will be easily decomposed by the action of hydrogen fluoride." These are party admissions that supply both the problem and the known class of solutions.

4. The differences between the prior art and the claims

Claim 1 differs from Demange only in:

1. the fluorinating agent is Ishikawa reagent rather than DAST; and
2. a hydrogen fluoride-scavenger is present.
   (The "reaction solvent" limitation is met by Demange's DCM-based process and is trivial.)

Everything else — trans-4-hydroxy-L-proline derivative with R¹ = α-amino protecting group and R² = carboxyl protecting group; conversion to the cis-4-fluoro product with inversion and no epimerization — is disclosed by Demange, which uses exactly the Boc/Fmoc, methyl-ester substrates recited downstream in claims 2–3.

5. Combinations that render the claims obvious

Combination A (primary): Demange + Ishikawa reagent (known alternative) + NaF HF-scavenger (known technique)

• Motivation to substitute Ishikawa for DAST. KSR rationale (1): "simple substitution of one known element for another," and (2) "use of a known technique to improve similar [methods] in the same way." DAST and Ishikawa reagent are interchangeable dehydroxyfluorinating agents; the art expressly frames Ishikawa reagent as the stable, inexpensive alternative to DAST. The specification itself supplies the industrial motivation (DAST toxic, heat-unstable, explosive, expensive). A PHOSITA pursuing an industrial route to cis-4-fluoroproline from Demange would predictably reach for Ishikawa reagent.
• Motivation to add the HF scavenger. KSR rationale: the HF byproduct and its damaging effects were known (specification admission; general knowledge re: HF handling with Yarovenko/Ishikawa reagents). NaF is a known HF scavenger, and Exfluor US 4,859,747 teaches adding an HF scavenger to a fluorination reaction specifically to eliminate HF, improve yield, and prevent HF from attacking the substrate. The nature of the problem itself → obvious solution. Reasonable expectation of success: trapping the acid with NaF predictably reduces acid-mediated decomposition of Boc/urethane groups.
• "Obvious to try." The dehydroxyfluorinating agents form a small, finite, predictable class (DAST, Deoxo-Fluor, Ishikawa, Yarovenko), and in-situ HF scavenging by NaF/KF is a known adjunct. Under KSR, trying Ishikawa with an HF scavenger was within the routine choices of a PHOSITA.

Combination B: Demange + Giardina

Giardina shows the alternative leaving-group route and its β-elimination failure mode, confirming the desirability of direct dehydroxyfluorination (which is why the art had moved to DAST/Ishikawa-type reagents). This strengthens the motivation to use an aminotrifluoroalkyl (Ishikawa/DAST) reagent rather than the leaving-group route.

Combination C: Degussa '234 + Demange + HF-scavenger knowledge

Degussa '234 confirms the pyrrolidine-2-carboxylate scaffold (with N-/C-protection) as a known intermediate class, supplying the reason to make the fluorinated proline (useful as a synthetic intermediate), i.e., motivation/utility. It is a supporting, not a primary, reference.

6. Claim-by-claim conclusion

Net: all seven claims are vulnerable under § 103, with claims 1 and 4–7 being the most exposed (the narrow claims recite the most conventional species choices, which are themselves the most predictable).

7. Secondary considerations (objective indicia) — counterweights

For patentability (non-obviousness arguments the patentee could raise):

1. Unexpected results / dramatic effect. Table 1 shows 14% (Ishikawa alone) vs. 85% (with NaF) yield, and 85% again with only 1.2 eq reagent at 21 °C in 8 h. Enabling room-temperature operation and reduced reagent loading is real practical benefit.
2. Long-felt, unmet need / enablement of urethane-protected substrates. Prior art required low temperature/long time because Boc groups decompose under HF; the invention makes Boc-protected substrates work under mild conditions — an industrial-enabling advance.
3. Teaching away (weak). A PHOSITA might worry that adding fluoride ion could quench/consume the amine-based fluorinating reagent; the prior art's insistence on low-temperature/short-time conditions could be read as teaching that the substrate—not the HF—was the problem.

Why these are weakened:

• The "unexpected" comparison is against Ishikawa-alone (14%), not against the closest prior art (Demange/DAST, 81%). The claimed 85% is essentially the same yield the art already achieved with DAST, so the invention shows no meaningful yield advantage over the best prior art — the improvement is in safety/processing, not in an unexpected chemical outcome. Under KSR, improvement over the closest art, not over an inferior embodiment, is what matters.
• The yield gain from removing a known acid-mediated decomposition pathway is arguably predictable in kind; the art (Exfluor '747) already taught that scavenging HF in fluorinations improves yield and prevents substrate attack. That is a strong teaching toward, not away.
• Commercial-success/long-felt-need arguments will face nexus problems given Demange already delivered the protected cis-4-fluoro-L-proline.

8. Bottom line

• Primary § 103 combination: Demange (1998) as the closest art, in view of the known Ishikawa reagent as a DAST substitute, and in view of known HF-scavenging with NaF (e.g., Exfluor US 4,859,747), motivated by the known HF-decomposition problem the specification itself admits. This renders claim 1 obvious; the dependent claims fall with routine, predictable selections.
• Secondary combinations: + Giardina (1995) and/or US 6,384,234 for motivation/utility.
• The strongest residual non-obviousness argument is the dramatic in-situ improvement over Ishikawa-alone and the mild-condition enablement of urethane-protected substrates — but its force is materially undercut because the closest prior art (Demange/DAST) already achieved ~81%, so there is little unexpected chemical result versus the best art.

Caveats / uncertainties

• JP 2006103986 A is listed on the page but is post-critical-date and non-analogous (cement); I do not treat it as citable art.
• US 6,384,234 and JP 2002275267 A are only tangentially relevant; the § 103 case rests mainly on Demange + known Ishikawa reagent + known HF-scavenger practice.
• Whether a specific combination would prevail depends on the actual claim construction and on whether the patentee can adduce nexus-bearing objective evidence; this is a predictive analysis, not a determination. The patent expired 2011-10-09 (fee lapse), which limits—but does not eliminate—the practical stakes of a validity challenge.