Synthesis of optically active 1,2,5-trimethyl-4-ethynyl-4-piperidols and the corresponding diacetylenic glycols

Abstract

The following optically active enantiomeric pairs were synthesized by the Favorskii reaction from (+)-(2S,5R)- and (−)-(2R,5S)-trans-1,2,5-trimethyl-4-piperidones: (+)-(2S,4R,5R)- and (−)-(2R,4S,5S)-trans-1,2,5-trimethyl-4-ethynyl-4-piperidol and (+)-(2S,4S,5R)- and (−)-(2R,4R,5S)-trans-1,2,5-trimethyl-4-ethynyl-4-piperidol. Optically active 1,4-bis(1,2,5-trimethyl-4-hydroxy-4-piperidyl) buta-1,3-diynes were obtained by Glaser oxidative dimerization of the enantiomeric pairs of ethynylpiperidols. The antagonistic action of the dihydrochlorides of (+)-(2S,4R,5R)- and (−)-1,4-bis[(2R,4S,5S)-1,2,5-trimethyl-4-hydroxy-4-piperidyl]buta-1,3-diyne on cell respiration was established from the results of biological tests on cultures of tobacco and Chlorella cells.