Lock and Key
Lock and Key 1
an1.AsymmetricInduction
1. Asymmetric Induction 2
Modern concept of assymmetric inductionCNCN1HCNR*CHO+HC-OH +HO-CH11R*R*川I三HONCCNOHssm$SSSSSE1E2E'1E'2*R*RE = Nonbonded interaction energyWhen R* is dissymmetric,E2 + E'2E, + E'i3
Modern concept of assymmetric induction E = Nonbonded interaction energy When R* is dissymmetric, E1 + E'1 E2 + E'2
The preferential metabolismofthe dextro-enantiomer of tartaric acid is 15 years priortoFischer'sdoctoralstudiesCOOHCOOHCOOH111H-C-OHHO-C-HPenicilliumHO-C-H++FermentationproductsHO-C-HH-C-OHH-C-OHglaucum1COOHCOOHCOOHNaturalUnnaturaldl-TartaricacidI-TartaricacidFiG.2.LouisPasteur's preparation ofD-(levo)-tartaric acid
The preferential metabolism of the dextroenantiomer of tartaric acid is 15 years prior to Fischer’s doctoral studies
Anunderstandingof optical isomerismhadbeenprovidedin1874byvan'tHoff-LeBeltheory ofasymmetric carbonDissymmetricPlane of symmetryCOOHCOOHCOOHCOOH.HO-C-HH-C-OHHO-C-HH-CC-OH主HO-C-HHO-C-HH-C-OHH-C-OHCOOHCOOHCOOHCOOHMesoRacemateFiG.3.-Thebasic assumption forFischer's researchof the optical isomerism of sugarsAll previousobservationsinthesugargroup are insuchcomplete agreement with the theory ofasymmetric carbon thattheuseofthistheory seems justifiable
An understanding of optical isomerism had been provided in 1874 by van’t Hoff – Le Bel theory of asymmetric carbon All previous observations in the sugar group are in such complete agreement with the theory of asymmetric carbon that the use of this theory seems justifiable