121331-22-4

Upstream product

• 2627-86-3 (S)-1-phenyl-ethylamine 
• 91424-40-7 3-(tert-butyldimethylsilyloxy)glutaric anhydride 
• 223437-45-4 (S)-5-((S)-4-Benzyl-2-oxo-oxazolidin-3-yl)-3-(tert-butyl-dimethyl-silanyloxy)-5-oxo-pentanoic acid ((S)-1-phenyl-ethyl)-amide 

Downstream Products

• 121331-23-5 (3S,1'S)-3-[[(1,1-Dimethylethyl)dimethylsilyl]oxy]-5-[(1-phenylethyl)amino]-5-oxopentanoic acid, methyl ester 
• 121331-24-6 (R)-3-(tert-Butyl-dimethyl-silanyloxy)-4-((S)-1-phenyl-ethylcarbamoyl)-butyric acid methyl ester 
• 573690-18-3 (3S)-3-{[(tert-butyl)dimethylsilyl]oxy}-N¹-methoxy-N¹-methyl-N⁵-[(1S)-1-phenylethyl]pentanediamide 
• 134208-74-5 (3S,1'S)-3-hydroxy-5-<(1-phenylethyl)amino>-5-oxopentanoic acid, dicyclohexylamine salt 
• 121331-26-8 C₂₀H₃₂N₂O₅Si 
• 134208-73-4 (S)-3-Hydroxy-4-((S)-1-phenyl-ethylcarbamoyl)-butyric acid 

Relevant academic research and scientific papers

A new and efficient synthesis of the HMG-CoA reductase inhibitor pitavastatin

A new synthetic method for the preparation of pravastatin is described. The approach circumvents various synthetic problems associated with the buildup of the 3,5-dihydroxy-C7 acid side chain of HMG-CoA reductase inhibitors (statins). The use of the C6-amide derivative 5 instead of ester derivatives in the coupling reaction with carboxaldehyde 8 (Scheme 3) prevents undesired side reactions, such as eliminations and retro-aldol reactions. The method provides synthetic statins, such as pitavastatin, in >99% ee and exceptionally high overall yield. The enantiomerically pure starting material, (3S)-3-{[(tert-butyl)dimethylsilyl]oxy}-5-oxo-5-{[(1S)-1-phenylethyl]amino} pentanoic acid (3c), is prepared by an improved procedure from 3-{[(tert-butyl)dimethylsilyl]oxy}glutaric anhydride (1) and (1S)-1-phenylethylamine (2c; Scheme 1).

Desymmetrization of prochiral anhydrides with Evans' oxazolidinones: An efficient route to homochiral glutaric and adipic acid derivatives

The prochiral recognition between enantiotopic carbonyl groups in the reaction of 3-substituted glutaric and 3,4-disubstituted adipic anhydrides with anions of Evans' oxazolidinones has been investigated. Each of the σ-symmetric anhydrides provided a diastereoisomeric mixture of half-acids which were separated either by fractional crystallization or by column chromatography of their esters. The diastereoselectivity of the desymmetrization reaction is dependent on the substituents present in the anhydrides.