Anthraquinones structure-activity relationship

Lemus, R. H. Skibo, E. B. Design of pyritnido[4.5-s quinazoline-based anthraquinone mimics, structure-activity relationship for quinone methide formation and the influence of internal hydrogen bonds on quinone methide fate. J. Org. Chem. 1992, 57, 5649-5660. 

Kuo et al., [18] investigated the structure-activity relationships of anthraquinones on intestinal motility, using rabbit small intestinal strips. This study revealed the critical requirement of a hydroxy group at 2 position, whereas the presence of other polar groups at this position, such as an amino, aldehyde and carboxylic acid groups, significantly reduced the activity. The presence of a methyl group and esterification of the carboxylic acid at 2 position was found to abolish the activity. 

ABSTRACT This paper attempts to present a review on the study of phytochemical and pharmacological activities of plants from the genus Hedyotis (Rubiaceae) in the last seven decades, which include our work on Malaysian Hedyotis species. The structure-activity relationships of compounds isolated from this genus are compiled and discussed. Finally, there is also a brief discussion on the biosynthesis of anthraquinones, iridoid glycosides and alkaloids, which are the common constituents of Hedyotis species. 

Anthraquinones are metabolically active and are frequently transformed by fungal enzymes into xanthones, e.g., ravenelin (Birch et aL, 1976) and tajixanthone (Holker et al, 1974), and into secalonic acids (Franck, 1969), (Kurobane et al., 1978). The biosynthetic relationship between versicolorin A and sterigmatocystin is indicated by their structural similarity, their cooccurrence in several fungi, and also the fact that their absolute configurations are identical (Gorst-Allman et al, 1978). In aflatoxin biosynthesis, a... 

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