CAJ | 학술논문

在B3 LYP/6-31 G**水平下优化了几种B环间位取代异黄酮衍生物的几何构型,在B3 LYP/6-311G**水平下计算了该类化合物的核磁共振谱.研究结果表明:在1E～1H和2E ～ 2H中的分子内氢键,其键长为0.1668nm,使整个分子形成一个四环的交叉共轭体系.从9位羟基取代对异黄酮衍生物NMR数据的影响来看,相邻的碳和相邻的氢化学位移的减少是由于电子云密度的增加和屏蔽作用的加强.而相邻碳的化学位移增加更大.此外,从取代基对化学位移的影响进行了讨论.邻对位氢的化学位移与取代基使苯环电子云密度增大的趋势相一致.A环和C环上的氢基本不受取代基的影响.对位碳的化学位移则与取代基使苯环电子云密度增大的趋势相反,邻位碳的化学位移变化趋势不明显.
재B3 LYP/6-31 G**수평하우화료궤충B배간위취대이황동연생물적궤하구형,재B3 LYP/6-311G**수평하계산료해류화합물적핵자공진보.연구결과표명:재1E～1H화2E ～ 2H중적분자내경건,기건장위0.1668nm,사정개분자형성일개사배적교차공액체계.종9위간기취대대이황동연생물NMR수거적영향래간,상린적탄화상린적경화학위이적감소시유우전자운밀도적증가화병폐작용적가강.이상린탄적화학위이증가경대.차외,종취대기대화학위이적영향진행료토론.린대위경적화학위이여취대기사분배전자운밀도증대적추세상일치.A배화C배상적경기본불수취대기적영향.대위탄적화학위이칙여취대기사분배전자운밀도증대적추세상반,린위탄적화학위이변화추세불명현.
Eight kinds of isoflavone derivatives with meta-substituent on B ring have been optimized at B3LYP/6-31G * * level.At B3LYP/6-311 G* * level and by GIAO method,NMR spectra of the title compounds have been studied.The results show that the Intramolecular hydrogen bonding has been formed in 1E ～1H and 2E ～ 2H compounds whose bond length is about 0.2773nm.NMR spectra characteristics of the compounds with 9-hydroxyl substituting hydrogen have been discussed.The chemical shifts of adjacent carbon and adjacent hydrogen decrease owing to increase of electron cloud density and strengthening of shielding effect.However,the chemical shift of the conjoint carbon has more increase.In addition,the effects of substituents on the chemical shift have been discussed.The chemical shifts of ortho-and para-hydrogens increase along with strengthening of substituent groups'supplying electron to benzene.Substituent groups have little effect on hydrogens of A and C rings.The chemical shift of para-carbon increases as substituent groups'supplying electron to benzene increases.The chemical shift of ortho-carbon hasn't a distinct change rule.