Sulfogriseofulvin Derivatives. Synthesis by [4+2]Cycloaddition, Structure, Properties, Crystal Structure Analysis, and Antifungal Activity of Spiro[1,3‐benzoxathiole‐2,1′‐cyclohex‐2′‐en]‐4′‐one 3,3‐Dioxides

Abstract

Syntheses of substituted, especially of fluoro substituted benzoxathiole 1,1-dioxides, are described. These derivatives were transformed via the Peterson olefination into substituted 2-alkylidene derivatives 27. Diels-Alder reactions of 27 with 1,1-dimethoxy- and 1-methoxy-3-trimethylsiloxy-1,3-butadiene (30, 32) gave sulfone analogues 31 of griseofulvin (named sulfogriseofulvins). From Z-27, a number of cis-isomers with the relative stereochemistry of griseofulvin (cis-31) was prepared, and from E-isomers of 27, compounds (trans-31) with relative stereochemistry of epigriseofulvin were obtained. Some related compounds (33, 38) are synthesized by slight modifications. The stereochemistry is established by spectroscopic methods and crystal structure analyses. The compounds 31 were tested against three species of dermatophytes. The biological activities were all significantly lower than that of griseofulvin.

Antifungal Activity of Griseofulvin Derivatives against Phytopathogenic Fungi in Vitro and in Vivo and Three-Dimensional Quantitative Structure–Activity Relationship Analysis

“…All of these compounds, 2 intermediates, and the newly prepared 19 derivatives were confirmed by 1 H and 13 C NMR and MS as well as HRESIMS spectral data. Of the 22 analogues, 17 compounds (3b−3g, 5, 6a−6c, 6e−6k, and 7) are new based on searching in SciFinder web.…”

“…Griseofulvin ( 1 ; Scheme ), a spirocyclic benzofuran-3-one natural antifungal product, was initially isolated from Penicillium griseofulvum in 1939 by Oxford et al It was the first oral antifungal drug in the treatment of dermatomycoses, such as tinea capitis (ringworm of the scalp) and tinea pedis (athlete’s foot), in animals and humans for decades. − Griseofulvin has gained a lot of attention in research and academic circles; , more than 400 griseofulvin analogues have been synthesized and used for drug screening. − In addition to the antifungal effect, griseofulvin exhibits various other biological activities, including anticancer and antiviral properties. Moreover, it is also useful against plant pathogenic fungi. − Zhao et al reported that griseofulvin displayed clear inhibition of the growth of eight different plant pathogenic fungi. In our previously reported study, griseofulvin, as an isolated natural product, showed significant inhibitory activity against the pathogenic fungus Alternaria solani …”

Doped Keggin heteropolyacids as catalysts in sulfide oxidation

“…They can be used as intermediates for pharmaceuticals and pesticides, and for the modification of polymers [17,18]. Certain sulfones are effective herbicides and others act as insecticides, and acaricides [19]; certain heterocyclic sulfones can be used as corrosion protection agents for metals [20].…”

1H and 13C NMR spectral study of some 3‐aryl‐5r‐aryl‐6t‐carbethoxycyclohex‐2‐enones—a study of four‐bond 1H1H couplings

“…Cyclohex‐2‐enones are useful in the synthesis of organic compounds 1–5. Cyclohex‐2‐enone derivatives exhibit antifungal6 and anticancer7 activities. However, to our knowledge only two NMR spectral studies8, 9 have been reported on cyclohex‐2‐enones.…”