741682-85-9

Upstream product

• 33537-18-7 cyclopentyl-oxo-acetic acid ethyl ester 
• 873-77-8 (4-chlorphenyl)magnesium bromide 
• 34966-48-8 ethyl 2-(4-chlorophenyl)-2-oxoacetate 
• 32916-51-1 cyclopentylmagnesium chloride 

Downstream Products

• 92021-41-5 (4-chlorophenyl)cyclopentylhydroxyacetic acid 

Relevant academic research and scientific papers

Carry over of impurities: A detailed exemplification for glycopyrrolate (NVA237)

The original synthesis of glycopyrrolate (NVA237) was revised and shortened into an essentially one-pot process. Without isolating the intermediates, their purification became obsolete, thereby increasing the possibility of the carry over of impurities. For that reason, the actual, potential, and theoretical impurities of the starting materials cyclopentyl mandelic acid and 1-methyl-pyrrolidin-3-ol as well as byproducts which may occur during the synthesis were thoroughly investigated; furthermore, their transformation to possible impurities in the drug substance along the new synthetic route was performed to exclude them as actual impurities in the drug substance with certainty. The question is raised how detailed such investigation-which are fairly manageable for a simple product like glycopyrrolate-need to be.

MELANIN-CONCENTRATING HORMONE RECEPTOR ANTAGONISTS CONTAINING PIPERIDINE DERIVATIVES AS THE ACTIVE INGREDIENT

The invention provides melanin-concentrating hormone receptor antagonists containing as the active ingredient piperidine derivatives represented by the general formula [I]: ???[wherein R1 is hydrogen, hydroxyl, lower alkyl, or the like; R2, R3a, R3b, R4a, R4b, R5a, R5b and R6 each stands for hydrogen, halogen, or the like; W1 and W2 each independently stands for -O-, -CH2-, or the like; Y1, Y2, Y3 and Y4 stand for -CH-, -CF-, -N-, or the like; Z stands for lower alkyl, an aliphatic heterocyclic group, or the like; Ar is a mono- or bi-cyclic aliphatic heterocycle or an aromatic heterocycle; and n is an integer of 1 to 8]. The compounds act as antagonist against melanin-concentrating hormone receptor and are useful as drugs for central diseases, circulatory diseases, or metabolic diseases.