Penicillium roqueforti structure

In 1976 Scott et al. (186) isolated the neurotoxin roquefortine (144) from the fungus Penicillium roqueforti. Structure 144 was deduced on the basis of spectroscopic data and degradative products. The alkaloid appeared to be the same as roquefortine C, isolated by Ohmomo et al. in 1975 (187). The latter authors confirmed the structure by spectroscopic evidence (188) they also isolated roquefortine D. Reduction of roquefortine D with zinc in acetic acid yielded two dihydro derivatives. The properties of roquefortine C and of one of the isomers correlated very well. Thus, roquefortine D is dihydro-roquefortine C (189). The stereochemistry still remains to be solved. 

These alkaloids possess most unusual structural features, namely the 1-methoxyindoline ring, the two nitrogen atoms directly attached to position 2 of this ring, giving a triaminomethane type of structure, and a dimethylallyl group at position 3 of the indole system. A related alkaloid, roquefortine, has been isolated (76E140) from Penicillium roqueforti, but does not possess a 1-methoxyl group. 

CARUTHERS, J. M., KANG, I., RYNKIEWICZ, M. J., CANE, D. E., CHRISTIANSON, D. W., Crystal structure determination of aristolochene synthase from the blue cheese mold, Penicillium roqueforti, J. Biol. Chem., 2000, 275, 25533-25539. 

A second stereoselective total synthesis of ( )-eremophilone (243) has been accomplished using 7-epinootkatone (242) as intermediate.109 The latter compound was synthesized from (—)-/3-pinene (241) by modification of the published procedure"0 and subsequently converted into eremophilone (243) by the series of functional-group transformations shown in Scheme 30. A mycotoxin isolated from Penicillium roqueforti has been assigned the highly oxygenated eremophilane structure (244) on the basis of chemical and spectroscopic evidence."1 The structure and... 

The authors speculate about the incorporation of the reverse prenyl unit in this and related molecules such as echinulin, lanosulin, oxaline, austamide, and the brevianamides and infer the rearrangement of the N-prenyl to the reverse 2-prenyl structure as shown in Scheme 22. These workers investigated the involvement of the 2-position of the indole by deuterium labeling using an auxotrophic mutant strain of Penicillium roqueforti that was apparently deficient in anthranilate synthetase. 

Polonsky, J., Merrien, M.A., Prange, P., Pascard, C., and Moreau, S. (1980) Isolation and structure (X-ray analysis) of macfortine A, a new alkaloid from Penicillium roqueforti. J. Chem. Soc. Chem. Commun., 601-602. 

In 1976, two new nitrogen-containing metabolites were isolated from the mycelium of Penicillium roqueforti. The major metabolite was designated roquefortine and assigned structure 22 based on chemical and spectroscopic evidence. The minor metabolite was shown to be a stereoisomer of a known alkaloid, fumigaclavin A. Roquefortine possessed neurotoxic properties and caused convulsions in experimental animals. The LD50 to male mice was 15-10 mg/kg on i.p. injection (Scott et al., 1976). 

Citrinin (9.22) is a widespread mycotoxin that is formed by many Penicillium and Aspergillus species, particularly P. citrinum, P. expansum and P. roqueforti. It was first isolated in 1931 by the Raistrick group and described as an antibiotic. It has been shown to have carcinogenic effects and to produce kidney damage. Evidence for its structure and biosynthesis is discussed in Chapter 4. 

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