贝母辛的结构修正

REVISION OF STRUCTURE OF PEIMISINE

从川产家种华西贝母(Fritillaria siechuanica)鳞茎中分出贝母辛(peimisine)(碱Ⅲ)。应用光谱法(~1H—~1H,^(13)C—~1H COSY,2D—NOE),对文献报告的贝母辛的结构作了修正,并证明FR—5与贝母辛系同一化合物。指出湖贝辛结构的某些错误以及对松贝辛的结构提出怀疑,认为其可能为贝母辛。

From the bulbs of Fritillaria siechuanica cultivated in Sichuan province,5 alkaloids including peimisine (Ⅲ) were isolated. Structure of peimisine reported inreference(2 )was revised as 2 based on 2D- NMR (~1H - ~1H,~1H - ^(13)C COSY and NOE ), andFR- 5 was proved to be peimisine on the basis of their melting point and TLC behavior.It is worthy of noting that 1)configuration of the oxygen at the C-17 in hupehenisine 3is possibly erroneous; 2) both songbaisine 4(A or B ) and peimisine 2 should be the samecompound on the basis of comparison of their ^(13)C NMR data(Table 3 ) and ~1H NMRspectra; 3)configuration of the oxygen atom at C- 17 in the jervine- type steroidal alkalo-ids can not be safely proved by their IR, MS and the chemical shifts of some protons suchas the methyls without the X-ray diffractionn analysis, or the NOE technique and the^(13)C NMR method.