236406-08-9

Upstream product

• 75-77-4 chloro-trimethyl-silane 
• 930-30-3 cyclopent-2-enone 
• 116907-30-3 (2R,5R)-2-(tert-butyl)-5-phenyl-1,3-dioxolan-4-one 

Downstream Products

• 203321-56-6 (2R)-2-[(1R)-3,3-difluorocyclopentyl]-2-hydroxy-2-phenylacetic acid 
• 236406-09-0 (2R,5R)-2-tert-butyl-5-[(1R or 1S)-3-oxocyclopentyl]-5-phenyl-1,3-dioxalan-4-one 
• 203321-54-4 (2R,5R)-2-(t-butyl)-5-[(1S)-3-oxocyclopentyl]-5-phenyl-1,3-dioxolan-4-one 
• 203321-55-5 (2R,5R)-2-(tert-butyl)-5-[(1R)-3-oxocyclopentyl]-5-phenyl-1,3-dioxolan-4-one 
• 328583-82-0 (2R,5R)-2-tert-butyl-5-(3-oxo-1-cyclopentyl)-5-phenyl-1,3-dioxolan-4-one 

Relevant academic research and scientific papers

N-acyl cyclic amine derivatives

The invention relates to compounds represented by the general formula [I][wherein Ar means an aryl group or a heteroaryl group which may have a substitutive group selected from a group consisting of a halogen atom, a lower alkyl group and a lower alkoxy group; R1 means a C3-C6 cycloalkyl group which is substitutable with a fluorine atom; R2 and R4 mean hydrogen atoms, groups represented by -(A1)m-NH-B or the like; R3 and R5 mean hydrogen atoms, C1-C6 aliphatic hydrocarbon groups or the like which are substitutable with a lower alkyl group(s); n means 0 or 1; and X means an oxygen atom or a sulfur atom]. Compounds according to the invention, since they not only have potent selective antagonistic activity against muscarinic M3 receptors but also exhibit excellent oral activity, durability of action and pharmacokinetics, are very useful as safe and effective remedies against respiratory, urinary and digestive diseases with little adverse side effects.

Diastereoselective synthesis of the acid part of a new muscarinic M3 receptor antagonist

Diastereoselective synthesis of (2R)-2-[(1R)-3,3-difluorocyclopentyl]-2-hydroxy-2-phenylacetic acid 1, an important component of a novel muscarinic M3 receptor antagonist 3, was achieved via Michael addition of an enolate of chiral dioxolane 4 to (-)-dicyclopentadiene 9 in 90% de as a key step. The desired Michael adduct 10, which was easily isolated by recrystallization of a mixture of diastereomers, was submitted to retrograde Diels-Alder reaction. Subsequent hydrogenation of the resultant enone 12 gave the key intermediate 5 in 91% chemical yield from 10. (C) 2000 Elsevier Science Ltd.