In the mol-ecules of both (E)-1-{3-[(5-fluoro-2-hy-droxy-benzyl-idene)amino]-phen-yl}ethanone, C15H12FNO2, (I), and (E)-1-{3-[(2-hy-droxy-3-meth-oxy-benzyl-idene)amino]-phen-yl}ethanone, C16H15NO3, (II), which crystallizes with Z' = 2 in space group Pca21, there are intra-molecular O-H⋯N hydrogen bonds, and the non-H atoms in each mol-ecule are essentially coplanar. In the crystal of (I), mol-e...

The megaloblastic anemia of cobalamin deficiency appears secondary to decreased methionine synthetase activity. Decreased activity of this enzyme should cause 5-methyltetrahydrofolate to accumulate intracellularly, and consequently, decrease purine and DNA synthesis; this is the basis of the "methylfolate trap" hypothesis of cobalamin deficiency. However, only some of the clinical and biochemic...

Difluorocarbene, generated from trimethylsilyl fluorosulfonyldifluoroacetate (TFDA), reacts with the uridine and adenosine substrates preferentially at the enolizable amide moiety of the uracil ring and the 6-amino group of the purine ring. 2',3'-Di-O-acetyl-3'-deoxy-3'-methyleneuridine reacts with TFDA to produce 4-O-difluoromethyl product derived from an insertion of difluorocarbene into the ...

1-alkyl aryl-5-amino-4-(cyanoformimidoyl)imidazoles 4 were reacted with malononitrile and 2-amino-1,1,3-propenetricarbonitrile under mild experimental conditions, which led to 5-amino-3-(substituted benzyl)-6,7-dicyano-3H-imidazo[4,5-b]pyridines 5 and 6,8-diamino-3-(4-substituted benzyl)-3H-imidazo[4,5-b]-1,8-naphthyridine-7,9-dicarbonitrile 6, respectively, when the reaction was carried out in...

3. The enzyme system could be concentrated from growth media, though with some loss, by ammonium sulphate precipitation. 4. Of the substances tested, all the primary aromatic alcohols, which included fi-naphthylcarbinol, benzyl alcohol and seven other ringsubstituted benzyl alcohols, were oxidized, but three secondary I-phenylethanols were not. Glucose, ethanol, butanol and the L-amino acids te...

Three cysteine derivatives, (R)-S-(2-hydroxyethyl)cysteine, together with (R(S)R(C))- and (S(S)R(C))-S-(2-hydroxyethyl)cysteine sulfoxides, have been isolated from the roots of Petiveria alliacea. Furthermore, three additional amino acids, S-methyl-, S-ethyl-, and S-propylcysteine derivatives, were detected. They were present only in trace amounts (<3 microg g(-1) fr. wt), precluding determinat...

There is considerable evidence that a critical reaction in purine synthesis is the closure of the purine ring by the addition of a “formate” group to 4-amino-5-imidazolecarboxamide ribonucleotide (1). Apparently the “formate” is added as an active intermediate, since formate as such has little effect in stimulating purine synthesis. Indeed, there is a demonstrable difference in the utilization ...

The metabolic profiles of Cordyceps bassiana according to fruiting body developmental stage were investigated using gas chromatography-mass spectrometry. We were able to detect 62 metabolites, including 48 metabolites from 70% methanol extracts and 14 metabolites from 100% n-hexane extracts. These metabolites were classified as alcohols, amino acids, organic acids, phosphoric acids, purine nucl...