Pterin structures reactions

Pterin, 5-formyl-6,7-dimethyl-5,6,7,8-tetrahydro-structure, 3, 281 Pterin, 6-hydroxymethyl-reactions, 3, 304 structure, 3, 273 Pterin, 7-hydroxymethyl-synthesis, 3, 311... 

FIGURE 18.35 Formation of THF from folic acid by the dihydrofolate reductase reaction. The R group on these folate molecules symbolizes the one to seven (or more) glutamate units that folates characteristically contain. All of these glutamates are bound in y-carboxyl amide linkages (as in the folic acid structure shown in the box A Deeper Look Folic Acid, Pterins, and Insect VFingis). The one-carbon units carried by THF are bound at N, or at or as a single carbon attached to both... 

Pterin-4-one, 2-amino-structure, 3, 273 Pterin-7-one, 2,4-dimethoxy-hydrolysis, 3, 299 Pterin-6-ones reactions... 

Stronger chemical evidence for the presence of a dithiolene in molybdopterin was obtained when the mild alkylation reagent iodoacetamide effectively trapped the dithiolene (65). This reaction yielded a derivative whose characterization by FAB mass spectrometry and nuclear magnetic resonance (NMR) was consistent with the structure shown in Fig. 5. The method appeared to leave the side chain intact and preserved the pterin oxidation state. From this experiment the view persisted that molybdopterin is a disubstituted dithiolene bearing a reduced pterin and a short chain terminated with a phosphate. 

---