Tosylhydrazones. VIII. Preparation of conjugated dienes from tosylhydrazones of .alpha.,.beta.-unsaturated ketones and alkyllithium reagents

Dauben, William G.; Lorber, Milton E.; Vietmeyer, Noel D.; Shapiro, Robert H.; Duncan, Joseph H.; Tomer, Kenneth B.

doi:10.1021/ja01019a065

Cited by 72 publications

(22 citation statements)

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“…Consequently, it was decided to use a BamfordStevens-Shapiro reaction (38,39). Reduction of 19-THP-19-hydroxyandrostenedione (12) (30) with LiAl (O-t-butyl)3H (31) gave the known (30) 19-THP-19-hydroxytestosterone (13).…”

Section: Resultsmentioning

confidence: 99%

Conversion of a 3-desoxysteroid to 3-desoxyestrogen by human placental aromatase.

Cole

Bean

Robinson

1990

Proc. Natl. Acad. Sci. U.S.A.

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Human placental aromatase is a cytochrome P.450 enzyme system which converts androgens to estrogens by three successive oxidative reactions. The first two steps have been shown to be hydroxylations at the androgen 19-carbon, but the third step remains unknown. A leading theory for the third step involves ferric peroxide attack on the 19-oxo group to produce a 19,19-hydroxyferric peroxide intermediate and subsequent collapse to estrogen. We had previously developed a nonenzymatic peroxide model reaction which was based on the above-mentioned theory, and we demonstrated the importance of 3-ketone enolization in facilitating aromatization. This study discusses the synthesis and nonenzymatic and enzymatic study of a 3-desoxy-2,4-diene-19-oxo androgen analogue. This compound was found to be a potent nonenzymatic model substrate and competitive inhibitor of aromatase (K1 = 73 nM).Furthermore, in an unprecedented event, this compound served as a substrate for aromatase, with conversion to the corresponding 3-desoxyestrogen.

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Section: Resultsmentioning

confidence: 99%

Conversion of a 3-desoxysteroid to 3-desoxyestrogen by human placental aromatase.

Cole

Bean

Robinson

1990

Proc. Natl. Acad. Sci. U.S.A.

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“…Compounds 4 and 5 were prepared by the reaction of singlet oxygen with 1-methyl-4-isopropenyl-2,6-cyclohexadiene (11), 8) which was synthesized by the conversion of carvone to the corresponding tosylhydrazone followed by treatment with methyl lithium. In order to introduce the acetoxy group on the 2-position of the cyclohexenyl ring of 4 and 5, the precursor 1-methyl-2-acetoxy-4-isopropenyl-2,6-cyclohexadiene (12) 9) was prepared by the reaction of carvone with isopropenyl acetate.…”

Section: )mentioning

confidence: 99%

“…The precursor compounds, 1-methyl-4-isopropenyl-2,6-cyclohexadiene (11), 1-methyl-2-acetoxy-4-isopropenyl-2,6-cyclohexadiene (12), 4-isopropyl-1,3-cyclohexadiene-carboxylic acid (13), 4-isopropyl-1,3-cyclohexadiene-1-methanol (14), and 4-isopropyl-1,3-cyclohexadienecarboxylic acid methyl ester (15) were prepared following published procedures. [8][9][10][11] 2. General synthetic procedure for ascaridole (1) and its derivatives (2-10) To each precursor compound such as a-terpine and etc.…”

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confidence: 99%

Synthesis and nematocidal activity of ascaridole derivatives against Meloidogyne incognita and Aphelenchoides besseyi

2007

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A series of ascaridole derivatives 1-10 were successfully synthesized and their structures were characterized by 1 H, 13C NMR and high-resolution mass spectroscopy. The nematocidal activities of these compounds were evaluated and the results indicated that these derivatives have better nematocidal activities against Meloidogyne incognita than Aphelenchoides besseyi. Interestingly, cis-isomers of Z-3,6-epidioxy-1-methyl-4-isopropylcyclohexene (2) and Z-3,6-epidioxy-1-methyl-4-isopropenylcyclohexene (4) are more active than their corresponding trans-isomers. Among them, 1,4-epidioxy-4-isopropyl-2-cyclohexenoic acid (8) and 1,4-epidioxy-4-isopropyl-2-cyclohexenecarboxylic acid methyl ester (10) exhibited significant higher nematocidal activities than those of other analogs; therefore the carboxylic acid or carboxyl ester substituent on the ring might be essential for high nematocidal activity. Compared with the toxicity of a commercial nematocide, Oxamyl, these derivatives can be considered effective and promising.

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“…(5). Dauben et al ont toutefois montrC le r6le dtterminant de la sttrCochimie de l'hydrazone et de la nature du solvant (6).…”

Section: Introductionunclassified

Substitution régiosélective d'arènesulfonylhydrazones α,β-insaturées via la réaction de Shapiro

Caille¹,

Farnier²,

Guilard³

1986

Can. J. Chem.

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Tosylhydrazones. VIII. Preparation of conjugated dienes from tosylhydrazones of .alpha.,.beta.-unsaturated ketones and alkyllithium reagents

Cited by 72 publications

References 0 publications

Conversion of a 3-desoxysteroid to 3-desoxyestrogen by human placental aromatase.

Conversion of a 3-desoxysteroid to 3-desoxyestrogen by human placental aromatase.

Synthesis and nematocidal activity of ascaridole derivatives against Meloidogyne incognita and Aphelenchoides besseyi

Substitution régiosélective d'arènesulfonylhydrazones α,β-insaturées via la réaction de Shapiro

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