146236-45-5Relevant academic research and scientific papers
Total synthesis of the major metabolites of gomisin A. Synthesis of homochiral met A-II, met A-III, met D, and met F
Tanaka, Masahide,Mitsuhashi, Hiroshi,Marano, Masao,Wakamatsu, Takeshi
, p. 359 - 374 (2007/10/02)
The total syntheses of the metabolites of gomisin A (1) were achieved. By the Mukaiyama hydration or the successive double bond migration, lactone ring reduction, glycol formation, and reduction, the homochiral lactones (10a-c) provided met A-III (3), A-II (2), D (5), and F (7).
Total Syntheses of the Metabolites of Schizandrin
Tanaka, Masahide,Ikeya, Yukinobu,Mitsuhashi, Hiroshi,Maruno, Masao,Wakamatsu, Takeshi
, p. 11703 - 11724 (2007/10/02)
The total syntheses of the metabolites of schizandrin were achieved.The tetracyclic lactone intermediates (13a-e) were prepared in optically pure form by the oxidative coupling reaction of the corresponding 3-benzyl-2-benzylidenebutyrolactones.Mukaiyama hydration of 13b afforded hydroxylactone (14), which was converted into SZ-M3 (4).The introduction of C6,7-diol moiety, which is common to the metabolites (4-11), was carried out by the successive double bond migration to 15a-e, lactone ring reduction ot the allylic diols (32a-e), and glycol formation.Then, reduction of the mesylates 33 completed the syntheses of the metabolites.
Synthesis of optically pure gomisi lignans: The total synthesis of (+)-schizandrin, (+)-gomisin A, and (+)-isoschizandrin in naturally occurring forms
Tanaka,Mukaiyama,Mitsuhashi,Maruno,Wakamatsu
, p. 4339 - 4352 (2007/10/02)
The total syntheses of (+)-schizandrin (1), (+)-gomisin A (2), and (+)-isoschizandrin (3) having natural configurations were accomplished. Optically pure butyrolactones ((-)-9, (-)-31) were transformed to α-benzylidenebutyrolactones ((+)-10, (+)-32, (+)-35). By a highly efficient iron(III) perchlorate-mediated oxidative coupling reaction of 10, 32, and 35, the key intermediates with biphenyl skeletons ((-)-11, (-)-33) were constructed with high stereoselectivity. Several methods for the stereoselective introduction of the C6-hydroxyl group were examined. For the synthesis of schizandrin and gomisin A, the Mukaiyama hydration reaction of (-)-11 and(-)-33 provided the desired products with satisfactory selectivity. For the synthesis of isoschizandrin, the stereoselective epoxidation of allylic alcohol (+)-48 was successfully utilized taking advantage of its conformational features.
Process for the preparation of polycyclic compounds using ferric perchlorate and acid trifluoroacidic
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, (2008/06/13)
Polycyclic compounds (I) can be prepared in accordance with the following reaction formula: STR1 wherein R1 -R8 each represents a hydrogen atom, a hydroxyl group, an alkoxyl group or a substituted or unsubstituted benzyloxy group or
Polycyclic compounds, their preparation and their use as phosphodiesterases inhibitors
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, (2008/06/13)
Polycyclic compounds (I) can be prepared in accordance with the following reaction formula: wherein R1-R8 each represents a hydrogen atom, a hydroxyl group, an alkoxyl group or a substituted or unsubstituted benzyloxy group or neighb
Synthesis of optically pure gomisin A and schizandrin: The first total synthesis of gomisin A and schizandrin having naturally occurring configurations
Tanaka,Mukaiyama,Mitsuhashi,Wakamatsu
, p. 4165 - 4168 (2007/10/02)
The total synthesis of gomisin A and schizandrin having natural configurations were accomplished for the first time. The key feature of these syntheses is a highly efficient intramolecular oxidative coupling of the intermediates 9 and 21, which can be obtained as both enantiomers in optically pure forms. The manipulation of the lactone moieties of 7 and 22 afforded natural enantiomers of schizandrin and gomisin A.
