Enzymes in organic synthesis. 37. Preparation and characterization of potential decalindione substrates of horse liver alcohol dehydrogenase

Abstract

. 65, 2397 (1987).The preparations of ten decalindiones for investigation as substrates of horse liver alcohol dehydrogenase are reported The structure characterizations include clarifications of some ambiguities in the decalin literature.J. BRYAN JONES et DAVID R. DODDS. Can. J. Chem. 65, 2397Chem. 65, (1987.On a prtpark dix dtcalinediones dans le but d'examiner leur comportement comme substrats de la dkshydrogknase d'alcool provenant du foie de cheval. Les caractkrisations de leurs structures a permis de clarifier quelques ambiguitks que l'on retrouve dans la littkrature relativement aux dkcalines.[Traduit par la revue]The ability of enzymes to catalyze stereospecific transformations of symmetrical substrates into chiral synthons of value in asymmetric synthesis is now well established (2). Stereospecific oxidations of a broad structural range of meso diols catalyzed by horse liver alcohol dehydrogenase (HLADH) represent one of the most dramatic illustrations of this approach to chiral synthon preparation (3). The complementary process of chiron production via stereospecific reductions of symmetrical diketones is of equal asymmetric synthetic interest. As the first step in evaluating this aspect of HLADH stereospecificity we initiated an investigation of the enzyme's catalysis of the reductions of a series of the potential decalindione substrates 1-10 and oxidation of the meso diol 11.

Spirocyclic Nitroxide Biradicals: Synthesis and Evaluation as Dynamic Nuclear Polarizing Agents

“…13 C‐NMR (100 MHz, CDCl 3 ): 209.4; 44.0; 39.1; 38.0; 32.8; 27.1. These spectral characteristics matched those previously reported in the literature [38] …”

Total Synthesis and Biological Evaluation of 19-Hydroxysarmentogenin-3-O-α-l-rhamnoside, Trewianin, and Their Aglycons

“…After acetylation of the remaining C19-primary alcohol of 15, oxidative cleavage of the C3-isopropenyl group of 16 by combining OsO 4 and NaIO 4 , followed by the Baeyer−Villiger reaction of the methyl ketone of 17 with m-CPBA, The trans-fused AB-ring 10b was synthesized from 22, which originated from commercially available 21 by applying a known 3-step protocol (Scheme 2B). 23 Enantioselective acetylation of the C3-hydroxy group under Momose's conditions (lipase AK and vinyl acetate in i-Pr 2 O at 35 °C) 24 converted meso-diol 22 into monoacetylated 23 in an enantiopure form (>99% ee). p-Methoxybenzyl (PMB) protection of the C7-hydroxy group using 4-methoxybenzyl-2,2,2-trichloroacetimidate and camphorsulfonic acid (CSA) 25 afforded 24, and NaAlH 2 (OCH 2 CH 2 OCH 3 ) 2 (Red-Al) reduced the C10-ethoxy carbonyl group of 24 to the primary hydroxy group of 25.…”

“…The trans -fused AB-ring 10b was synthesized from 22 , which originated from commercially available 21 by applying a known 3-step protocol (Scheme B) . Enantioselective acetylation of the C3-hydroxy group under Momose’s conditions (lipase AK and vinyl acetate in i -Pr 2 O at 35 °C) converted meso -diol 22 into monoacetylated 23 in an enantiopure form (>99% ee).…”

Toosendanin: Synthesis of the AB-ring and investigations of its anti-botulinum properties (Part II)

“…This compound is readily available in large scale, from commercially available starting materials ( 8 and 9 ) by a two-step modification as detailed by Jones and Dodds 13. Thus, upon benzylation of the hydroxy group found within 10 under acidic conditions,14 the resulting ketone was protected as the ketal ( 11 ) in 51% yield for the two steps.…”

“…Catalytic amount of trifluoromethanesulfonic acid was added to a solution of (2 RS ,4a RS ,8a SR )-ethyl 2-hydroxy-7-oxodecahydronaphthalene-4a-carboxylate ( 10 )13 (1.37 g, 5.7 mmol) and benzyl 2,2,2-trichloroacetimidate (1.2 mL, 6.3 mmol) in cyclohexane (20 mL) and CH 2 Cl 2 (10 mL) at room temperature, and the mixture was stirred at room temperature for 9 h. The precipitate was filtered off, and the filtrate was washed with sat. NaHCO 3 aq.…”