A general method for the asymmetric synthesis of both enantiomers of 1-substituted 1,2,3,4-tetrahydro-β-carbolines employing pyroglutamic acid derivatives as chiral auxiliaries
9-(S)-Pyroglutaminyl-β-carbolines were allowed to react with a nucleophile (allyltributyltin or a silyl enol ether) in the presence of 2,2,2-trichloroethyl chloroformate to give 1,2-addition products in good yields and high diastereoselectivity. The chiral auxiliary at N-9 was readily removed by a mild hydrolysis. The same chiral source afforded both enantiomers by simply altering a protecting group of the amide nitrogen. That is, (S)-pyroglutaminyl groups which had an N-alkyl group afforded the (S) isomer, whereas the ones having an N-acyl group produced the (R) isomer of the addition products.
A new entry to asymmetric synthesis of 1-substituted 1,2,3,4-tetrahydro-β-carbolines employing a pyroglutamic acid derivative as a chiral auxiliary
β-Carboline which was protected at N-9 by an acyl group derived from L-pyroglutamic acid reacted with allyltributyltin or silyl enol ethers in the presence of an alkyl chloroformate in a highly diastereoselective manner to give 1-substituted 1,2-dihydro-β
Get Best Price for474433-43-71-Allyl-9-((S)-1-benzenesulfonyl-5-oxo-pyrrolidine-2-carbonyl)-1,9-dihydro-β-carboline-2-carboxylic acid 2,2,2-trichloro-ethyl ester