163660-01-3

Upstream product

• 79755-69-4 5-((1S,2R)-2-Hydroxy-1-methyl-propyl)-4-methyl-benzene-1,3-diol 
• 16051-42-6 (+/-)-threo-2,6-dihydroxy-4-(2-hydroxy-1-methylpropyl)-3-methylbenzoic acid 
• 124-38-9 carbon dioxide 
• 518-75-2 citrinin 

Downstream Products

• 518-75-2 citrinin 
• 79755-69-4 5-((1S,2R)-2-Hydroxy-1-methyl-propyl)-4-methyl-benzene-1,3-diol 
• 102553-87-7 (3R)-1ξ-benzyl-6,8-dihydroxy-3r,4t,5-trimethyl-isochroman-7-carboxylic acid 
• 109560-19-2 (3R)-6,8-dihydroxy-3r,4t,5-trimethyl-1ξ-phenyl-isochroman-7-carboxylic acid 
• 102019-04-5 (3R)-8-hydroxy-3r,4t,5-trimethyl-6-oxo-1-phenyl-4,6-dihydro-3H-isochromene-7-carboxylic acid 

Relevant academic research and scientific papers

Citrinin revisited: From monomers to dimers and beyond

Detailed chemical analysis of the solid phase fermentation of an Australian Penicillium citrinum isolate has returned the known compounds citrinin (1), phenol A acid (6), dihydrocitrinone (7) and dihydrocitrinin (8), together with a novel cytotoxic dimer, dicitrinin A (5). Dicitrinin A (5) was determined to be a dimerised artefact of the major co-metabolite citrinin, and its structure solved by spectroscopic analysis and chemical modification. Analysis of the products encountered during the controlled decomposition of citrinin led to the discovery of additional citrinin dimers and delineated a plausible mechanistic pathway linking all monomeric and dimeric citrinin degradation products. The Royal Society of Chemistry 2006.

Enantioselective Synthesis of the Polyketide Antibiotic (3R,4S)-(-)-Citrinin

The fungal metabolite (-)-citrinin (1) was synthesized for the first time.Reaction of the Grignard reagent of 2,4-bis(benzyloxy)-6-bromotoluene (3) with (2S)-trans-(-)-2,3-dimethyloxirane (6) in the presence of 1,5-cyclooctadienecopper(I) chloride as catalyst leads to the formation of (2S,3S)-(-)-7 with erythro configuration.Compound (-)-7 could be transformed into (2R,3S)-(-)-9 with threo configuration via the formate (1R,2S)-(+)-8 by a Mitsunobu reaction.Reaction of the Grignard reagent of 3 with the achiral cis-2,3-dimethyl-oxirane yielded directly (+/-)-9.The starting material 3 was readily available from 1,3-bis(benzyloxy)-5-bromobenzene (4).Formylation of 4 furnished the aldehyde 5 which could be reduced to 3 with borane.Hydrogenolysis of the benzyl ether groups in (-)-9 gave (-)-2 with threo configuration.The remaining steps to produce citrinin from (-)-2 required carboxylation to 11, formylation and in situ ring closure with ethyl orthoformate to produce the required quinomethide structure.Application of the same reactions to (+/-)-9 and (+/-)-2 afforded (+/-)-citrinin in 40percent overall yield. - Key Words: Citrinin, (3R,4S)-(-)- / 2,3-Dimethyloxirane, trans-(-)- and cis- / Synthesis of erythro- and threo-3-arylbutan-2-ols