Heptachloro-1 -methyl-1,2 -bipyrrole

Wu J, Vetter W, Gribble GW, Schneekloth Jr. JS, Blank DH, Gorls H (2002) Structure and Synthesis of the Natural Heptachloro-1 -methyl-1,2 -bipyrrole (Ql). Angew Chem Int Ed 41 1740... 

All three techniques have been unequally exemplified in the separation of heterocyclic atropisomers. GC on a 10% permethyl-(-cyclodextrin (Chirasil-Dex, Chrompack) chemically bonded to a dimethyl polysiloxane backbone (CB-(-PMCD) coupled with El—MS was employed to elucidate the structure of a hexachlorinated bipyrrole which was obtained as a byproduct during the synthesis of the achiral heptachloro-1 ( -methyl-1,2 ( -bipyrrole (02AC4287). Two baseline separated peaks were obtained in ca. 20 min confirming the chiral structure of the by-product. 

Vetter and Jun have elucidated the structure of an hexachlorinated by-product obtained during the S5uithesis of the heptachloro 1 -methyl-1,2 -bipyrrole 337. Among the three possible structures, 341 may give atropenantiomers, whereas 339 and 340 are achiral. The GC analysis on 10% permethyl-p-cyclodextrin (Chirasil-Dex, Chrompack) chemically bonded to a dimethyl polysiloxane backbone (CB-p-PMCD) coupled with EI-MS revealed two peaks that confirm the chirality of the product (02AC4287). 

S., Vatter, S., Chahbane, N., Lenoir, D., Schramm, K.W. and Scherer, G. (2005) Biological activity and physicochemical parameters of marine halogenated natural products 2,3,3, 4,4, 5,5 -heptachloro-l -methyl-1,2 -bipyrrole and 2,4,6-tribromoanisole. Archives of Environmental Contamination and Toxicology, 48, 1-9. 

Vetter W, Jun W, Althoff G (2003) Non-Polar Halogenated Natural Products Bioaccumulated in Marine Samples. I. 2,3,3 ,4,4 ,5,5 -Heptachloro-l -methyl-l,2 -bipyrrole (Ql). Chemosphere 52 415... 

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