A novel conformationally restricted analogue of 3-methylaspartic acid via stereoselective methylation of chiral pyrrolidin-2-ones
摘要:
Conformationally restricted analogues of beta-methylaspartic acid were easily prepared starting from chiral N-protected trans-3-amino-4-methoxycarbonyl pyrrolidin-2-ones. The key step of the synthesis was the methylation reaction at CA, proceeding with high diastereoselection syn to the protected amino group lying at C-3 of the pyrrolidin-2-one ring. (C) 2009 Elsevier Ltd. All rights reserved.
A novel conformationally restricted analogue of 3-methylaspartic acid via stereoselective methylation of chiral pyrrolidin-2-ones
摘要:
Conformationally restricted analogues of beta-methylaspartic acid were easily prepared starting from chiral N-protected trans-3-amino-4-methoxycarbonyl pyrrolidin-2-ones. The key step of the synthesis was the methylation reaction at CA, proceeding with high diastereoselection syn to the protected amino group lying at C-3 of the pyrrolidin-2-one ring. (C) 2009 Elsevier Ltd. All rights reserved.
Centre refold: (3R,4S,1′S)‐4‐Amino‐1‐(1′‐(4‐methoxyphenyl)ethyl)‐3‐methyl‐5‐oxopyrrolidine‐3‐carboxylic acid (AMMOPC) gives a foldamer with an 8‐helix conformation. When it was inserted in the 12‐helix foldamer of (3R,4S,1′S)‐4‐amino‐1‐(1′‐(4‐methoxyphenyl)ethyl)‐5‐oxo‐pyrrolidine‐3‐carboxylic acid (AMOPC), it locally induced formation of an 8‐helix conformation (see figure).