Monocrotalic acid从脱氢野百合碱的释放及其鉴定

目的：为进一步研究野百合碱的代谢和毒理，制备其相应的代谢产物。方法：采用氮氧化和脱氢化反应将野百合碱分别转化为其氮氧化物和脱氢产物，其中后者在氯仿溶液中发生水解并释放出一个酸性化合物。结果：所得3个化合物经UV，IR，MS和NMR分析确证为dehvdromonocrotaline，monocrotaline N-oxide和monocrotalic acid。结论：Monocrotalic acid为首次从野百合碱的吡咯酯(dehydromonocrotaline)的自然降解中获得，但未同时得到其碱基部分dehydroretronecine，这证明了吡咯里西啶生物碱的吡咯酯具有很高的化学反应活性，故在代谢研究中往往不是直接的代谢产物；对所得3种化合物的氢谱和碳谱数据首次进行了全归属。

Release and Identification of Monocrotalic Acid from Dehydromonocrotaline

AIM: To prepare the corresponding metabolite s of monocr otaline for further investigation of its metabolism and toxicology ME TH OD: Two chemical procedures involving N-oxidation and dehydrogenat ion were applied to convert monocrotaline into its N-oxide and dehydromonocrot aline respectively The latter released monocrotalic acid rapidly and automatic ally i n chloroform solution containing trace of water or acid under normal condition RESULT: Three compounds were determined by UV,IR,MS and extensive u se of NMR techniques CONCLUSION: Monocrotalic acid was obtain ed for the first time from monocrotaline pyrrole by an auto-catalytic process but d ehydroretronecine (the necine moiety) was not,which strongly proved that pyrrol ic ester was highly reactive and could not be detected as metabolite directly I n addition,the full assignments of NMR data for the above compounds were also r eported for the first time