A convenient synthesis of C-22 and C-25 stereoisomers of cephalostatin north 1 side chain from spirostan sapogenins

被引：49

作者：

Betancor, C

Freire, R

Pérez-Martín, I

Prangé, T

Suárez, E

机构：

[1] CSIC, Inst Prod Nat & Agrobiol, Tenerife 38206, Spain

[2] Univ Paris 11, LURE, F-91405 Orsay, France

[3] Univ La Laguna, Dept Quim Organ, Tenerife, Spain

来源：

ORGANIC LETTERS | 2002年 / 4卷 / 08期

关键词：

D O I：

10.1021/ol025580e

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

[GRAPHIC] A simple transformation of the eight-carbon side chain of a natural spirostan sapogenin into the cephalostatin north 1 spiroketal moiety is described. This methodology, based on an intramolecular hydrogen abstraction reaction promoted by alkoxy radicals, permits the synthesis of C-22 and C-25 stereoisomers of the dioxaspiro[4.4]nonane cephalostatin ring system. The acid-catalyzed isomerization of the spirocenter in the different isomers is studied.

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页码：1295 / 1297

页数：3

相关论文

共 26 条

[1] TRANSFORMATION OF STEROIDAL SAPOGENIN SIDE CHAIN .1. REACTIONS OF 9(11)-DEHYDROHECOGENIN ACETATE WITH NITROUS ACID AND WITH PARAFORMALDEHYDE [J].

BARTON, DHR ;

SAMMES, PG ;

TAYLOR, MV ;

WERSTIUK, E .

JOURNAL OF THE CHEMICAL SOCIETY C-ORGANIC, 1970, (14) :1977-&

[2] First total synthesis of an exceptionally potent antitumor saponin, OSW-1 [J].

Deng, SJ ;

Yu, B ;

Lou, Y ;

Hui, YZ .

JOURNAL OF ORGANIC CHEMISTRY, 1999, 64 (01) :202-208

[3] Syntheses of chiral dispiroacetals from carbohydrates [J].

Dorta, RL ;

Martín, A ;

Salazar, JA ;

Suárez, E ;

Prangé, T .

JOURNAL OF ORGANIC CHEMISTRY, 1998, 63 (07) :2251-2261

[4] Directed synthesis of nonsymmetrical bis-steroidal pyrazines and the first biologically active cephalostatin analogues [J].

Drogemuller, M ;

Jautelat, R ;

Winterfeldt, E .

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION IN ENGLISH, 1996, 35 (13-14) :1572-1574

[5]

Drögemüller M, 1998, EUR J ORG CHEM, V1998, P2811

[6]

Feray L., 2001, RADICALS ORGANIC SYN, V2, P246

[7] Isolation of 13 new ritterazines from the tunicate Ritterella tokioka and chemical transformation of ritterazine B [J].

Fukuzawa, S ;

Matsunaga, S ;

Fusetani, N .

JOURNAL OF ORGANIC CHEMISTRY, 1997, 62 (13) :4484-4491

[8] The dimeric steroid-pyrazine marine alkaloids: Challenges for isolation, synthesis, and biological studies [J].

Ganesan, A .

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION IN ENGLISH, 1996, 35 (06) :611-615

[9]

GONZALEZ AG, 1971, AN QUIM-INT, V67, P903

[10] NEW SOURCES OF STEROID SAPOGENINS .14. 25S-RUSCOGENIN AND SANSEVIERIGENIN, 2 NEW SPIROSTAN SAPOGENINS FROM SANSEVIERIA-TRIFASCIATA [J].

GONZALEZ, AG ;

FREIRE, R ;

GARCIAES.MG ;

SUAREZ, E ;

SALAZAR, JA .

TETRAHEDRON, 1972, 28 (05) :1289-&