ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Isolation and Structure Determination of the New Cyclosporins E, F, G, H und IThe cyclosporins, a new group of biologically active metabolites, are produced by the fungus Tolypocladium inflatum GAMS (formerly designated as Trichoderma polysporum [LINK EX PERS.] RIFAI). They represent neutral cyclic oligopeptides composed of 11 amino acids. In addition to the already described cyclosporins A-D new minor compounds, cyclosporins E-I, have now been isolated from the crude cyclosporin-complex by applying extensive chromatographical separation procedures. The structures of the new compounds have been determined by spectroscopical evidence, hydrolytic cleavage and chemical correlation reactions as well as by X-ray analysis of suitable derivatives. Cyclosporins A, B, C, D and G differ from each other only in the nature of the amino acid no. 2. Cyclosporins E and I are N-demethylated congeners of cyclosporins A and D respectively, Cyclosporin F has been recognized as deoxycyclosporin A, whereas Cyclosporin H represents an epimeric form of cyclosporin A and contains N-methyl-D-valine in position 11.
Additional Material:
10 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19820650538
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