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A stereoselective synthesis of phosphinic acid phosphapeptides corresponding to glutamyl-gamma-glutamate and incorporation into potent inhibitors of folylpoly-gamma-glutamyl synthetase.

ABSTRACT: Radical addition of H3PO2 to N-/C-protected vinyl glycine led to the corresponding H-phosphinic acid in excellent yield. The non-nucleophilic H-phosphinic acid was converted to a nucleophilic P(III) species, RP(OTMS)2, which was used in two approaches to the target phosphinic acid containing pseudopeptide. New methodology was developed that led to excellent yields in the reaction of RP(OTMS)2 with unactivated electrophiles, including an acyclic homoallylic bromide. However, en route to the target pseudopeptide, Arbuzov reaction of RP(OTMS)2 with a cyclic homoallylic bromide, (R)-3-(bromomethyl)-cyclopent-1-ene, led to a rearranged allylic phosphinic acid rather than the desired homoallylic derivative, a putative glutarate surrogate. Conjugate addition of RP(OTMS)2 to alpha-methylene glutarate containing a chiral auxiliary resulted in only modest diastereoselectivity. Purification by flash chromatography provided protected derivatives of both diastereomers of the pseudopeptide. Following global deprotection, coupling of (S)-H-Glu-gamma-[Psi(P(O)(OH)(CH2))]-(S)-Glu-OH and (S)-H-Glu-gamma-[Psi(P(O)(OH)(CH2))]-(R)-Glu-OH to (4-amino-4-deoxy-10-methyl)pteroyl azide led to the target compounds for biochemical study as inhibitors of the ATP-dependent ligase, folylpoly-gamma-glutamate synthetase.

SUBMITTER: Bartley DM

PROVIDER: S-EPMC1989106 | biostudies-literature | 2005 Aug

REPOSITORIES: biostudies-literature

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A stereoselective synthesis of phosphinic acid phosphapeptides corresponding to glutamyl-gamma-glutamate and incorporation into potent inhibitors of folylpoly-gamma-glutamyl synthetase.

Bartley David M DM Coward James K JK

The Journal of organic chemistry 20050801 17

Radical addition of H3PO2 to N-/C-protected vinyl glycine led to the corresponding H-phosphinic acid in excellent yield. The non-nucleophilic H-phosphinic acid was converted to a nucleophilic P(III) species, RP(OTMS)2, which was used in two approaches to the target phosphinic acid containing pseudopeptide. New methodology was developed that led to excellent yields in the reaction of RP(OTMS)2 with unactivated electrophiles, including an acyclic homoallylic bromide. However, en route to the targe ...[more]

PMID: 16095295

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Dataset Information

A stereoselective synthesis of phosphinic acid phosphapeptides corresponding to glutamyl-gamma-glutamate and incorporation into potent inhibitors of folylpoly-gamma-glutamyl synthetase.

Publications

A stereoselective synthesis of phosphinic acid phosphapeptides corresponding to glutamyl-gamma-glutamate and incorporation into potent inhibitors of folylpoly-gamma-glutamyl synthetase.

Similar Datasets

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