Previous work in this laboratory (1) has shown that an increase in carbamyl phosphate synthetase activity in the livers of thyroxine-treated tadpoles is the result of protein synthesis de 1u)vo. This induction of the synthesis of a specific enzyme protein by thyroxine was found to be inhibited by chloramphenicol and thiouracil (2). A subsequent survey (3) of several purine and pyrimidine deriva...

The 5′-phosphate ester of 5-nitro-2′-deoxyuridine (7c) is a potent mechanism-based inhibitor of thymidylate synthase.2 Compound 7c3 and 1-(â-D-arabinofuranosyl)5-nitrouracil4 have antiviral activity, and certain O-nitro esters of pyrimidine5 and purine6 nucleosides also have biological activity. The 5′-O-nitro esters of pyrimidine nucleosides function as good substrates for 5′-modification via ...

BACKGROUND Cytidine and uridine are produced commercially by Bacillus subtilis. The production strains of cytidine and uridine were both derivatives from mutagenesis. However, the exact metabolic and genetic factors affecting the productivity remain unknown. Genetic engineering may be a promising approach to identify and confirm these factors. RESULTS With the deletion of the cdd and hom gene...

In vitro inhibition effects of indolylchalcones and new pyrido[2,3-d]pyrimidine derivatives on purified human carbonic anhydrase I and II (hCA I and II) were investigated by using CO2 as a substrate. The results showed that all compounds inhibited the hCA I and hCA II enzyme activities. Among all the synthesized compounds, 7e (IC50 = 6.79 µM) was found to be the most active compound for hCA I i...

Addition reactions of the C4'-C5' double bond of griseolic acid were investigated. C4'-C5' Dihydrogriseolic acid was obtained by reduction of the adduct having halogen at the 4'-position. The ring juncture of the two five-membered rings of the C4'-C5' dihydro derivatives was of all-"cis" configuration. Acetolysis of the protected dihydrogriseolic acid gave the corresponding 1 '-acetoxy sugar de...

This review describes the synthesis and evaluation of novel nucleic acid derivatives performed by our research group to date. We developed a new method for the synthesis of 2-alkoxyadenosine analogs via nonaqueous diazotization-dediazoniation reactions. By applying these reactions, we effectively synthesized four types of carbocyclic oxetanocin analogs (2-alkoxy-C.OXT-A). The angiogenic activit...

Transition metal-catalyzed halosulfonylation of 5-ethynyl uracil nucleosides provided (E)-5-(1-chloro-2-tosylvinyl)uridines. Tetrabutylammonium fluoride-mediated direct CH arylation of 5-iodouracil nucleosides with furan or 2-heptylfuran gave 5-furyl-substituted nucleosides without the necessity of using the organometallic substrates. These two classes of 5-substituted uracil nucleosides as we...

Human thymine-DNA glycosylase (TDG) is well known to excise thymine and uracil from G.T and G.U mismatches, respectively, and was therefore proposed to play a central role in the cellular defense against genetic mutation through spontaneous deamination of 5-methylcytosine and cytosine. In this study, we characterized two newly discovered orthologs of TDG, the Drosophila melanogaster Thd1p and t...