ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Investigation of the inhibition of δ-chymotrypsin with the four novel, optically active, axially and equatorially substituted cis-3-(2,4-dinitrophenoxy)-2,4-dioxa-3λ5-phosphabicyclo[4.4.0]decan-3-ones (= 3-(2,4-dinitrophenoxy)hexahydro-4H-1,3,2-benzodioxaphosphorin 2-oxides) showed only the equatorially substituted enantiomer (-)-4b to be an irreversible inhibitor of the enzyme, and (-)-4b at pH 7.8 revealed a quickly rising resonance at -2.49 ppm assigned to the hydrolysis product 8 and later, while inhibition proceeded, a second one at -4.08 ppm. attributed to the δ-chymotrypsin adduct 7 (Scheme 3). Comparision of the latter signal with the 31P-NMR chemical shifts of the covalent phosphoserine model compounds (-)-6a (-5.67 ppm, axial substitution) and (+)-6b (-4.02 ppm, equatorial substitution) suggests that the inhibition proceeded via neat retention of the configuration at the P-atom of (-)-4b yielding the equatorially substituted covalent Ser195 adduct 7.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19980810526
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