Neocarzinostatin chromophore: presence of a highly strained ether ring and its reaction with mercaptan and sodium borohydride.
Neocarzinostatin chromophore: presence of a highly strained ether ring and its reaction with mercaptan and sodium borohydride.
复制标题
新制癌菌素发色团：高度紧张的醚环的存在及其与硫醇和硼氢化钠的反应。
DOI：
10.1016/0006-291x(83)91759-x
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发表时间：
1983
影响因子：
3.1
通讯作者：
Goldberg,IH
中科院分区：
文献类型：
--
作者：
Hensens,OD;Dewey,RS;Liesch,JM;Napier,MA;Reamer,RA;Smith,JL;Albers-Schönberg,G;Goldberg,IH
光谱证据表明，在先前确定的主要新卡津抑素发色团(NCS-Chrom A)的部分结构2a(图2)的C12-亚单位中存在一个高度应变的醚环(图1)(可能是环氧化物)，这完成了分子中所有氧的指定。硫醇处理的主要产物是乙醚开环，包括一个硫醇分子的加成和C12亚结构的还原，而NaBH4处理则发生平行的两步还原。这两个反应都伴随着C12-亚结构的重排，并讨论了NCS-Chrom A在DNA链断裂活性中的作用机制。证据表明，NCS-Chrom A以及次要成分B和C的分子式向下修正了两个质子。
Spectroscopic evidence suggests the presence of a highly strained ether ring (Fig. 1)(possibly an epoxide) in the C 12-subunit of the previously determined partial structure 2a (Fig. 2) of the major neocarzinostatin chromophore (NCS-Chrom A) which completes assignment of all the oxygens in the molecule. The main product from mercaptan treatment suggests opening of the ether ring involving the addition of one molecule of mercaptan as well as reduction of the C 12-substructure, whereas a parallel two-step reduction occurs on NaBH 4 treatment. Both reactions occur with rearrangement of the C 12-substructure and the implication for the mechanism of action of NCS-Chrom A in DNA strand scission activity is discussed. The evidence suggests a downward revision of the molecular formula for NCS-Chrom A as well as minor components B and C by two protons.