2-Amino-6-nitro-benzoic acid → 2-methyl-5-nitro-4H-benzo[d][1,3]oxazin-4-one

Participants

Reaction Steps

In another embodiment, provided herein is a method for preparing 3-(5-amino-2-methyl-4-oxoquinazolin-3(4H)-yl)piperidine-2,6-dione, or an enantiomer or a mixture of enantiomers thereof; or a pharmaceutically acceptable salt, solvate, hydrate, or polymorph thereof; comprising the steps of (a) reacting 2-amino-6-nitrobenzoic acid with an activated acetic acid in a solvent to form 2-methyl-5-nitro-4H-benzo[d][1,3]oxazin-4-one; (b) reacting 2-methyl-5-nitro-4H-benzo[d][1,3]oxazin-4-one with 3-aminopiperidine-2,6-dione or a salt thereof in a solvent to form 3-(2-methyl-5-nitro-4-oxoquinazolin-3(4H)-yl)piperidine-2,6-dione; (c) reducing 3-(2-methyl-5-nitro-4-oxoquinazolin-3(4H)-yl)piperidine-2,6-dione in a solvent in the presence of formic acid to form N-(3-(2,6-dioxopiperidin-3-yl)-2-methyl-4-oxo-3,4-dihydroquinazolin-5-yl)formamide; and (d) hydrolyzing N-(3-(2,6-dioxopiperidin-3-yl)-2-methyl-4-oxo-3,4-dihydroquinazolin-5-yl)formamide in a solvent to form 3-(5-amino-2-methyl-4-oxoquinazolin-3(4H)-yl)piperidine-2,6-dione, or an enantiomer or a mixture of enantiomers thereof; or a pharmaceutically acceptable salt, solvate, hydrate, or polymorph thereof; wherein steps (a), (b), (c), and (d) are each as described herein elsewhere.

Provenance & Evidence