A CONVENIENT SYNTHESIS OF 7-ALPHA-HYDROXYCHOLEST-4-EN-3-ONE BY THE HYDROXYPROPYL-BETA-CYCLODEXTRIN-FACILITATED CHOLESTEROL OXIDASE OXIDATION OF 3-BETA,7-ALPHA-CHOLEST-5-ENE-3,7-DIOL

被引:34
作者
ALEXANDER, DL [1 ]
FISHER, JF [1 ]
机构
[1] UPJOHN LABS,KALAMAZOO,MI 49007
关键词
(7-ALPHA)-HYDROXYCHOLESTEROL; HYDROXYPROPYL-BETA-CYCLODEXTRIN; CHOLESTEROL OXIDASE; (7-ALPHA)-HYDROXYCHOLEST-4-EN-3-ONE; BILE ACID BIOSYNTHESIS; CHOLESTEROL; 7-ALPHA-HYDROXYLASE;
D O I
10.1016/0039-128X(95)93851-O
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The initial biosynthetic conversions of cholesterol to the bile acids involve sequential 7 alpha-hydroxylation (catalyzed by cholesterol 7 alpha-hydroxylase) followed by C-3 oxidation and concomittant double bond migration (to a Delta(4)-configuration, catalyzed by 3 beta-Delta(5)-C-27-steroid oxidoreductase) to provide 7 alpha-hydroxycholest-4-en-3-one. A straightforward, and economical, preparation (on a 0.1 g scale) of this pivotal biosynthetic intermediate has been devised. Reduction of 3 beta-(benzoyloxy)-cholest-5-en-7-one with LiB(sec-butyl)(3)H provided a 4:1 mixture, respectively, of the 7 alpha- and 7 beta-hydroxy diastereomers, which were separated chromatographically. Solvolytic removal of the C-3 benzoyl group gave 3 beta,7 alpha-cholest-5-ene-3,7-diol. A suspension of the 1:1 (nu/nu) complex (formed by mutual dissolution in MeOH, followed by evaporation of the solvent) of this diol with hydroxypropyl-beta-cyclodextrin, at a concentration of 1 mg mL(-1) (in neutral phosphate bl(buffer), was converted by Brevibacterium sp cholesterol oxidase (0.25 U mg(-1) of substrate) and catalase (70 U mg(-1) of substrate, to recover O-2 from the H2O2 produced by the enzymatic oxidation) to a suspension of 7 alpha-hydroxycholest-4-en-3-one and the hydroxypropyl-beta-cyclodextrin. The yield for the enzymatic conversion was in excess of 90%. A much poorer and less reproducible yield (<20%) was seen in the absence of the hydroxypropyl-beta-cyclodextrin. Routine extraction of this aqueous suspension, and chromatographic purification (85:15 CHCl3/acetone nu/nu on silica) of the residue, gave pure 7 alpha-hydroxycholest-4-en-3-one in 68% isolated yield. This route is a significant improvement, in terms of reaction scale and convenience, over the previous procedures for the preparation of this steroid.
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页码:290 / 294
页数:5
相关论文
共 44 条
[1]  
AMANN A, 1987, SYNTHESIS-STUTTGART, P1002
[2]   THE PLASMA-LEVEL OF 7-ALPHA-HYDROXY-4-CHOLESTEN-3-ONE REFLECTS THE ACTIVITY OF HEPATIC CHOLESTEROL 7-ALPHA-HYDROXYLASE IN MAN [J].
AXELSON, M ;
BJORKHEM, I ;
REIHNER, E ;
EINARSSON, K .
FEBS LETTERS, 1991, 284 (02) :216-218
[3]   POTENTIAL BILE-ACID PRECURSORS IN PLASMA - POSSIBLE INDICATORS OF BIOSYNTHETIC PATHWAYS TO CHOLIC AND CHENODEOXYCHOLIC ACIDS IN MAN [J].
AXELSON, M ;
SJOVALL, J .
JOURNAL OF STEROID BIOCHEMISTRY AND MOLECULAR BIOLOGY, 1990, 36 (06) :631-640
[4]  
AXELSON M, 1992, J BIOL CHEM, V267, P1701
[5]   A STEREOSELECTIVE SYNTHESIS OF 7-BETA-PHENYL AND 7-BETA-METHYLCHOLESTEROL [J].
BAKSHI, RK ;
RASMUSSON, GH .
TETRAHEDRON LETTERS, 1993, 34 (13) :2055-2058
[6]   THE MECHANISMS OF THE REARRANGEMENTS OF ALLYLIC HYDROPEROXIDES - 5-ALPHA-HYDROPEROXY-3-BETA-HYDROXYCHOLEST-6-ENE AND 7-ALPHA-HYDROPEROXY-3-BETA-HYDROXYCHOLEST-5-ENE [J].
BECKWITH, ALJ ;
DAVIES, AG ;
DAVISON, IGE ;
MACCOLL, A ;
MRUZEK, MH .
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2, 1989, (07) :815-824
[7]   CHOLESTEROL 7-ALPHA-HYDROXYLASE IS UP-REGULATED BY THE COMPETITIVE INHIBITOR 7-OXOCHOLESTEROL IN RAT-LIVER [J].
BREUER, O ;
SUDJANASUGIAMAN, E ;
EGGERTSEN, G ;
CHIANG, JYL ;
BJORKHEM, I .
EUROPEAN JOURNAL OF BIOCHEMISTRY, 1993, 215 (03) :705-710
[8]   SELECTIVE REACTIONS IN THE ANALYTICAL CHARACTERIZATION OF STEROIDS BY GAS-CHROMATOGRAPHY MASS-SPECTROMETRY [J].
BROOKS, CJW ;
COLE, WJ ;
LAWRIE, TDV ;
MACLACHLAN, J ;
BORTHWICK, JH ;
BARRETT, GM .
JOURNAL OF STEROID BIOCHEMISTRY AND MOLECULAR BIOLOGY, 1983, 19 (01) :189-201
[9]  
BYON CY, 1977, STEROIDS, V30, P419
[10]  
CHIANG JYL, 1994, J BIOL CHEM, V269, P17502