935544-54-0

Upstream product

• 181955-79-3 N,N'-di-tert-butyloxycarbonylpiperazine-2-carboxylic acid 
• 143540-05-0 2-hydroxymethylpiperazine-1,4-dicarboxylic acid di-tert-butyl ester 
• 216228-85-2 2-formylpiperazine-1,4-dicarboxylic acid di-tert-butyl ester 
• 847554-73-8 tert-butyl 3-oxo-1-phenyltetrahydro-1H-oxazolo[3,4-a]pyrazine-7(3H)-carboxylate 

Relevant academic research and scientific papers

An orthogonal protection strategy for the synthesis of 2-substituted piperazines

Tetrahydro-1H-oxazolo[3,4-a]pyrazin-3(5H)-ones are readily prepared from the bis-carbamate protected piperazine-2-carboxylic acids and serve as orthogonally protected piperazines from which a variety of 2-substituted piperazines can be prepared. Sodium benzylate and sodium phenoxides react at the C-5 carbon of the oxazolidinone to yield 2-(benzyloxymethyl)piperazines and 2-(phenoxymethyl)piperazines, respectively. The tetrahydro-1H-oxazolo[3,4-a]pyrazin-3(5H)-ones also provide convenient scaffolds from which 2-benzyl- and 2-phenethylpiperazines are prepared.

BICYCLIC PIPERAZINE COMPOUND AND USE THEREOF

The present invention provides a compound represented by the formula: wherein R1 is an acyl group, R2 is a hydrocarbon group which may be substituted or the like, R3 is a hydrocarbon group which may be substituted or the like, R4 is a hydrocarbon group which may be substituted or the like, n is from 0 to 4, and X is an oxygen atom, a sulfur atom or the like, or a salt thereof. The invention also provides a compound which has a TGR23 antagonist activity and thus is useful for prevention and treatment of cancer.