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Structural modifications of natural products with complex structures like steroids require great synthetic effort. A review of literature is presented on the chemistry of the steroidal hormone 17α-methyltestosterone that is approved by Food and Drug Administration (FDA) in the United States as an androgen for estrogen-androgen hormone replacement therapy treatment. The analog also offers special possibilities for the prevention/treatment of hormone-sensitive cancers. The testosterone skeleton has important functionalities in the molecule that can act as a carbonyl component, an active methylene compound, α,β-unsaturated enone and tertiary hydroxyl group in various chemical reactions to access stereoisomeric steroidal compounds with potent activity. In addition, microbiological methods of synthesis and transformation of this hormone are presented.

Simple, efficient, and catalyst-free syntheses of different heterocyclic systems incorporating chromone or related scaffolds are described using cascade reactions of 3-vinylchromone (III).

Phenolic OH groups can be selectively protected in the presence of aliphatic ones using sulfuryl imidazolium salts (I).

For the O-protection in carbohydrates or steroids, sulfurylimidazolium salts (II) having a methyl group at the 2-position of the imidazole ring are in general superior sulfating agents in comparison to analogues lacking the methyl group.

Condensation of different cyclic ketones with visnaginone 1a and khellinone 1b afforded spirofurochromanone derivatives 2a-f . Compounds 2a and 2b were readily demethylated to give the compounds 3a and 3b . Nitration of 2b and 2e gave the nitrofurochromonone and quinone derivatives 4 and 5 respectively. The chroman-4-ol derivatives 6a and 6b were obtained from reduction of 2b and 2e which were directly dehydrated to give compounds 7a and 7b respectively. Also, amide 6c was prepared which failed to provide 6d on acid hydrolysis. Bromination of the chromene 7a gave the corresponding 9-bromo derivative 7c and failed to give compound 8 . Treatment of 2b with NBS afforded the corresponding 2,9-dibromo derivative 10 . The chromanones 2b and 2e were reacted with hydroxylamine, phenyl hydrazine, aniline and paraformaldehyde to give the products 11a-e and 12a,b .

This study is directed towards the synthesis of the pyrrolo[1,2-α]indole skeleton which is the essential ring system of the active antitumor miomycins. To this end a number of fused heterocycles such as benzothiazines, benzoxazines, indoles and quinolines were synthesized. The structures of the new compounds were assigned by ir, 1H nmr and ms-data.

Selective incorporation of trichloroethyl (TCE)-protected sulfates into monosaccharides was examined using reagent 2. In general, sulfation of 4,6-O-benzylidene acetals of galactosides and glucosid...

Reaction of visnaginone which derived from the naturally occurring compound “visnagine”, with allyl bromide gave O-allyl visnaginone 1, which underwent Claisen rearrangement to yield 7-allylbenzofuran 2 derivative. Vilsmeier Haack formylation of 2 afforded our versatile starting compound furochromene-6-carboxaldehyde (3) which was condensed with cyclohexane-1,3-dione, indandione, malononitrile or ethyl cyanoacetate to yield the ylidene nicotinonitrile and pyridone derivatives 4,7,10a-b. Reaction of 3 with aniline or aniline acting on multiple function X-H (X = NH, O, S) at its ortho position afforded the corresponding anils, imidazolylfurochromene and azepines compounds 11-17. On the other hand, oxidation of visnagin afforded chromene-6-carboxaldehyde derivative 18 which was condensed with different aryl or (heteroaryl) acetonitrile followed by hydrolysis to give pyrano[3,2-g]chromen-4,8-dione derivatives 20a-d and 22.

Reaction of visnaginone 1 with allyl bromide gave O-allyl visnaginone 2 which underwent Claisen rearrangement to yield 7-allylbenzofuran derivative 3. Reaction of 3 with different aromatic aldehydes gave the corresponding 5-cinnamoylbenzofuran derivatives 4a-d. Condensation of the latter chalcones 4a,c,d with hydrazine hydrate and phenylhydrazine provided, the corresponding pyrazoline derivatives 7a-f. Claisen condensation of compound 3 with ethyl acetate and diethyl carbonate afforded Claisen adducts 8 and 12 which easily cyclized to 9 and 13, which are endowed with interesting biological properties.

Condensation of ketene dithioacetal derivatives with some aminoazoles (5-aminotetrazole monohydrate, 2-aminobenzimidazole, 2-aminobenzothiazole, and 2-aminothiazole) in the presence or absence of triethylamine gave the corresponding tetrazolopyrimidines, benzimidazopyrimidines, benzothiazolopyrimidines, and thiazolopyrimidines.

Reaction of different glycosyl donors with 5-hydroxy-N-methyl-2,3-diphenylindole (1C) led only to O-glycosylation (compounds 6a–c and 8c-α,β). Depending on the O-protection of the glycosyl donors (2a–c, 3b, 4c), the β-products were obtained mainly or exclusively. The corresponding N-unsubstituted indole 1B and donors 2b and 5a, respectively, also yielded only O-glycosylated products (compounds 11b and 13a). Depending on the glycosyl donor (2a or 2c), the N-unsubstituted 5-methoxy-2,3-diphenylindole (1A) led to N- and/or C-glycosides (compounds 16a, 14a-α,β, and 14c-α,β). The structures were assigned with the help of 1H-NMR data of these products or their derivatives.