Thioxanthenes, Thioxanthones, and Related Compounds

An X-ray crystallographic study of 9-isobutylthioxanthene 10,10-dioxide has been reported the central ring exists in a boat conformation, with the molecule folded about the S—C-9 axis. 

The action of alkalis on a series of thioxanthone 10,10-dioxides has been investigated the products include xanthones and the hydroxybenzo-phenone-sulphonic acids from which they are derived.  

Nasielski and G. Jacqmin, Tetrahedron, 1972,28, S97 G. Jacqmin, J. Nasielski, G. Billy, and M. Remy, Tetrahedron Letters, 1973, 3655. 

Kataoka, Y. Asahi, and E. Mizuta, Chem. and Pharm. Bull. (Japan), 1973, 21, 1415. 

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