Gentisyl alcohol

Dihydroxybenzyl alcohol (Gentisyl alcohol) [495-08-9] M 140.1, m 100° pKeskd 9.3, P st(2) ll 3. Crystd from CHCI3. Sublimes at 70° under high vacuum. 

A step in the biosynthesis of PATULIN (17) has been clarified by the finding that meta hydroxy benzyl alcohol is hydroxylated to yield gentisyl alcohol which in turn is converted to patulin via the aldehyde 55. 

A Chinese isolate of Penicillium terrestre derived from sediments yielded a series of new gentisyl alcohol polymers, including the trimeric terrestriol A (89) and the dimeric terrestrols B-H (90-96)/° All compounds showed moderate cytotoxicity toward four different cancer cell lines as well as moderate radical scavenging activity in the DPPH assay. Furthermore, 95 displayed moderate inhibitory activity against protein tyrosine kinases Src and KDR. 

Enzyme preparations from P. patulum have been obtained which have been studied for their substrate specificity and products formed. For example, one preparation converted m-hydroxybenzyl alcohol [3.43) into gentisyl alcohol [3.38) but the corresponding aldehyde [3.48) was not ring-hydroxylated by any preparation from P. patulum. Thus [3.43) but not [3.48) is on the pathway to patulin [3.45). All the various strands of evidence [32, 33] lead to the pathway shown in Scheme 3.8. 

The glycosides of salicyl and gentisyl alcohols in Salix spp. and Populus spp., genera of the Salicaceae family, have been extensively studied by Pearl et al. (124-130) and Thieme et al. (168-171) (see summary and references in ref. 123). Salicin (14), the glucoside of salicyl alcohol, occurs characteristically in this family of plants. This compound is found in the bark of all species in the family, but often in small amounts. Another characteristic compound of the many salicin-related compounds occurring in most Salix species is salicortin (15), in which the... 

Aromatic Cg. Ci aldehydes and alcohols are relatively infrequently encountered in higher plants and thdr occurrence has something of a novelty value. The most prominent of the Q. C, aldehydes is probably vanillin (105) and of the alcohols saligenin, as the /J-d-glucoside salicin (20), and the two glucosides of gentisyl alcohol (31 and 32) are certainly the most noteworthy. 

Ethyl [(4-oxo-2-phenyl-4/f-l- Fischer s base 7249 Gentisyl alcohol 6080... 

Birkinshaw, J. H., A. Bracken, and H. Raistrick Studies in the biochemistry of microorganisms. 72. Gentisyl alcohol, a metabolic product of Penicillium patulum Bainier. Biochem. J. 37, 726 (1943). 

Many other aromatic derivatives have been isolated from cultures of species of marine sediments. These include chlorinated derivatives of gentisyl alcohol from Penicillium terrestre (Chen et al, 2008) and naphtho-y-pyrone dimers from Aspergillus carbonarius (Zhang, Y. et al., 2008). Both species of fungi came from marine sediments of Chinese origin. 

Many biogenetic pathways have been proposed for the conversion of 6-MSA to patulin. In addition to 6-MSA (4) and patulin (1), P. patulum produces a variety of phenolic metabolites, some of which are represented in Fig. 7 6-formylsalicylic acid (5), m-cresol (6), m-hydroxybenzyl alcohol (7), gentisyl alcohol (8), gentisaldehyde (9), gentisic acid (10), and toluquinol (11). 

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