US 3371085

Patent Overview — US 3,371,085

Title: 5-aryl-3H-1,4-benzodiazepin-2(1H)-ones

Patent number: US 3,371,085 A

Assignee/Applicant: F. Hoffmann La Roche AG (original assignee). Application filed by F. Hoffmann La Roche AG; inventors Earl Reeder and Leo Henryk Sternbach.

Key dates (as listed): Priority date 1959-12-10; filing date 1961-11-20; publication/grant date 1968-02-27; expired — lifetime. The source also lists later reassignments (1981, 1983) to Curacao Pharmholding N.V. and Roche Products Inc., and an anticipated expiration of 1985-02-27.

Purpose: The invention "relates to novel 5-aryl-3H-1,4-benzodiazepin-2(1H)-ones, novel derivatives thereof and novel intermediates therefor; and processes of making the foregoing."

Plain-language scope (per the excerpt): The claims-language portion describes compounds of a general formula and their pharmaceutically acceptable salts, where:

• R is hydrogen, lower alkyl, lower alkenyl, lower alkynyl, aralkyl, or cyano-lower alkyl;
• R (second) is hydrogen, lower alkyl, lower alkoxy-lower alkyl, phenyl, or hydroxybenzyl;
• R, R, and R (ring substituents) are hydrogen, halogen, or lower alkyl;
• R (another) is hydrogen, lower alkyl, lower alkenyl, or lower alkynyl.

The compounds include 4,5-dihydro derivatives. Basic compounds form pharmaceutically acceptable acid addition salts with inorganic/organic acids (e.g., hydrochloric, sulfuric, tartaric, citric), and certain 4-position tertiary-amine compounds form quaternary ammonium salts with conventional quaternizing agents such as lower alkyl halides.

Processes described: Synthesis routes include reacting a 2-aminobenzophenone with hydroxylamine to form an oxime, acylation with an α-halo-lower alkanoyl halide in base, cyclization to a 5-phenyl-3H-1,4-benzodiazepin-2(1H)-one 4-oxide; reduction (phosphorus trichloride or hydrogen/Raney nickel); acid treatment of a 2-(N-methylacetamido) intermediate; reaction of a 2-aminobenzophenone with α-halo-lower alkanoyl halide followed by ammonia; and cyclization of 2-(aminoacetamido)benzophenones.

Source: https://patents.google.com/patent/US3371085/en

What the excerpt does not establish: Full claim text, the complete specification, all examples, exact formula drawings (chemical structures rendered as text are incomplete), the full class definitions, and any legal conclusions about validity, infringement, or claim scope.