Streptomyces pentalenolactone

In the course of biosynthetic experiments involving Streptomyces UC5319, Cane and Rossi treated the acidic fraction of an ether extract with diazomethane and obtained 600 which they called pentalenolactone E methyl ester Paquette s solution to the total synthesis of this substance (Scheme LI) was founded upon a... 

The fermentation broth of various Streptomyces species can be separated into an acidic fraction shown to contain pentalenic acid 776) The somewhat less oxidized pentalenolactone precursor has been independently prepared from humulene from which is is probably derived biogenetically Thus, treatment of humulene with mercuric nitrate followed by aqueous potassium bromide solution gave two bromo-mercury derivatives which were oxygenated in the presence of sodium borohydride. The resulting pair of diols (770 and 771) were separately converted to exo methylene... 

Although the first survey listed 45 natural chlorinated sesquiterpene lactones, several such compounds were omitted in that coverage (1) and are described here. The novel sesquiterpene lactone chlorochrymorin (239) was isolated from Chrysanthemum morfolium (499), and the chlorohydrin graminichlorin (240) is found in Liatris graminifolia (500). The antibacterial AA-57 (241), which is related to pentalenolactone, is produced by a Streptomyces sp. (501). The plant Eupatorium chinense var. simplicifolium has yielded eupachifolin D (242) (502) (side-chain double bond stereochemistry revised (518)), and the new guaianolide andalucin (243) was characterized from Artemisia lanata (503). The previously known chlorohyssopifolins (1) have been studied for cytostatic activity, and the presence of one and even two chlorine atoms amplifies this activity (504). 

Acidic lipophilic antibiotics pentalenolactones (69,70), active against Grampositive and Gram-negative bacteria including acid-fast bacteria, were isolated [68] from Streptomyces sp. 

Pentalenolactone is the name given to an antibiotic extracted from Streptomyces fungi with an Interesting tricyclic structure. 

The pentalane class of sesquiterpenoids has received substantial attention in the past year from the standpoints of structural elucidation, biosynthesis, and synthesis. Two new metabolites of this class are pentalenic acid (298) and pentalenolactone H (299). Both these compounds have a secondary hydroxyl function adjacent to the gem-dimethyl group and are thus potential precursors of pentalenolactone (300) in which one of these methyl groups has undergone a 1,2-migration. Cane and Rossi " have now identified a further metabolite of a Streptomyces strain which has been named pentalenolactone E (301) and is now... 

C15H24, Mr 204.36, oil, a sesquiterpene hydrocarbon of the triquinane type from cultures of Streptomyces griseochromogenes and S. UC 5319. It is the first isolable biosynthetic intermediate in the pathway from farnesyl pyrophosphate to the antibiotically active pentalenolactones. ... 

Pentalenolactones. A group of sesquiterpene antibiotics, P. A-P, from Streptomyces chromofuscus, S. arenae, S. omiyaensis, S. UC 5319, and others. ... 

Quaderer R, Omura S, Ikeda H, Cane DE (2006) Pentalenolactone biosynthesis. Molecular cloning and assignment of biochemical function to PtII, a cytochrome P450 of Streptomyces avermitilis. J Am Chem Soc 128 13036-13037... 

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