Chloramphenicol molecule has an asymmetric carbon, so it has conformational isomer, namely, threo and erythro form. These two forms have great difference in biological activity, that is, only threo (-) form has biological activity. Semiempirical quantum mechanical treatments are applied to these molecules to explain the difference, using the extended Huckel theory. The theoretical predictions for the preferred conformation are in good agreement with the experimental results.
Choloramphenicol분자에는 threo 및 erythro의 conformational isomer가 있고 biological activity가 아주 상이하여 threo(-)꼴만 biological activity가 있다. extended Huckel 이론을 사용 이들 분자들의 conformation을 계산하여 상기의 차이점의 이론적 설명을 꾀하였다.