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F F Fleming

Publications and source records attributed to F F Fleming.

5 recordsLinked to original sources
PubMed2000

gamma-hydroxy unsaturated nitriles: chelation-controlled conjugate additions.

[reaction--see text] Chelation between gamma-hydroxy unsaturated nitriles and Grignard reagents promotes an otherwise difficult anionic conjugate addition reaction. The intermediate chelate is readily generated by deprotonation with t-BuMgCl followed by the addition of a second Grignard reagent that triggers an intramolecular conjugate addition. Structurally diverse Grignard reagents add with equal efficiency, providing an intermediate anion that stereoselectively alkylates BnBr in an overall addition-alkylation reaction.

Drug Design↗
PubMed1999

beta-Siloxy unsaturated nitriles: stereoselective cyclizations to cis- and trans-decalins.

[formula: see text] beta-Siloxy unsaturated nitriles are excellent precursors to enolate and nitrile anions that cyclize to cis- and trans-decalins, respectively. The stereoelectronic requirements of endocyclic enolates and exocyclic nitrile anions are complementary, providing cis- and trans-decalins from a common intermediate. This cyclization allows the synthesis of diastereomeric cis- and trans-decalins containing a contiguous array of quaternary-tertiary-quaternary stereocenters.

Cyclization↗
PubMed1996

Fatty acid amide biosynthesis: a possible new role for peptidylglycine alpha-amidating enzyme and acyl-coenzyme A: glycine N-acyltransferase.

Fatty acid primary amides have recently been recognized as mammalian hormones [Cravatt et al. (1995) Science 268, 1506-1509]. The route to their biosynthesis is unknown. Many mammalian peptide hormones also possess a C-terminal alpha-amide moiety that arises from the posttranslational oxidative cleavage of a C-terminal glycine-extended precursor. The enzyme that catalyzes this reaction is peptidylglycine alpha-amidating enzyme, which is known to preferentially amidate peptide substrates containing a penultimate, hydrophobic amino acid [Tamburini et al. (1990) Int. J. Pept. Protein Res. 35, 153-156]. We show that N-myristoylglycine is a substrate for peptidylglycine alpha-amidating enzyme with a (V/K)app that is 55 +/- 4% of the value measured for D-Tyr-Val-Gly. N-Fatty acylglycines are enzymatically produced in mammals from fatty acyl-coenzyme A (CoAs) and glycine by acyl-CoA:glycine N-acyltransferase. The sequential actions of acyl-CoA:glycine N-acyltransferase and peptidyl-glycine alpha-amidating enzyme would lead to the biosynthesis of fatty acid amides.

Acyltransferases↗