ABSTRACT
Cyclic pyranopterin monophosphate (1), isolated from bacterial culture, has previously been shown to be effective in restoring normal function of molybdenum enzymes in molybdenum cofactor (MoCo)-deficient mice and human patients. Described here is a synthesis of 1 hydrobromide (1·HBr) employing in the key step a Viscontini reaction between 2,5,6-triamino-3,4-dihydropyrimidin-4-one dihydrochloride and D-galactose phenylhydrazone to give the pyranopterin (5aS,6R,7R,8R,9aR)-2-amino-6,7-dihydroxy-8-(hydroxymethyl)-3H,4H,5H,5aH,6H,7H,8H,9aH,10H-pyrano[3,2-g]pteridin-4-one (10) and establishing all four stereocenters found in 1. Compound 10, characterized spectroscopically and by X-ray crystallography, was transformed through a selectively protected tri-tert-butoxycarbonylamino intermediate into a highly crystalline tetracyclic phosphate ester (15). The latter underwent a Swern oxidation and then deprotection to give 1·HBr. Synthesized 1·HBr had in vitro efficacy comparable to that of 1 of bacterial origin as demonstrated by its enzymatic conversion into mature MoCo and subsequent reconstitution of MoCo-free human sulfite oxidase-molybdenum domain yielding a fully active enzyme. The described synthesis has the potential for scale up.
Subject(s)
Coenzymes/chemistry , Metalloproteins/chemistry , Organophosphorus Compounds/chemical synthesis , Pteridines/chemistry , Pterins/chemical synthesis , Coenzymes/metabolism , Escherichia coli/metabolism , Humans , Metalloproteins/metabolism , Molybdenum Cofactors , Organophosphorus Compounds/chemistry , Pteridines/metabolism , Pterins/chemistry , Signal Transduction , StereoisomerismABSTRACT
Kinetic resolution of racemic C-3 substituted pyrrolidine-2,5-diones has been achieved for the first time using highly efficient oxazaborolidine catalysts derived from cis-1-amino-indan-2-ol.
