5-Aryl-7-hydrazino-2-phenylpyrazolo[1,5-c]pyrimidines 1 were used as precursors for the preparation of a new series of 5-aryl-8-phenylpyrazolo[1,5-c]-1,2,4- triazolo[4,3-a]pyrimidines 2. The reactions of 2 with certain electrophilic reagents gave the respective 6-substituted derivatives 3-5 rather than the 7-isomeric products. Formylation of the key compounds 1 with ethyl formate yielded the fo...

Enzyme induction in Escherichia coli is stimulated by certain 5-amino-2,4-bis(substitutedamino)pyrimidines (Kunkee, 1960a). Other 2,4diaminopyrimidines have been reported to be antagonists of folic acid (Hitchings et al., 1952; Doctor, 1956). Since there are indications that the stimulation of enzyme induction involves nucleic acid metabolism (Kunkee, 1960b) and since folic acid is involved in ...

We present the first results from a time-dependent chemical model to include a gas-phase reaction scheme for producing doubly-deuterated species. Under normal conditions the formation of these species is inefficient. However, when the effects of the freeze out of gas phase species onto grains is included in the chemistry we find that the fractionation of both singly and doubly deuterated specie...

CH2D+, the singly deuterated counterpart of CH3(+), offers an alternative way to mediate formation of deuterated species at temperatures of several tens of Kelvin, as compared to the release of deuterated species from grains. We report a longstanding observational search for this molecular ion, whose rotational spectroscopy is not yet completely secure. We summarize the main spectroscopic prope...

A high-stability Eu-complex has been achieved by coating with a silica glass via a low temperature sol-gel process using deuterated methanol. A three-dimensional glass network protects Eu-complex from free-oxygen and/or water to change the ligand structure. In addition, the chemical bond of deuterated Eu-complex is more stable than that of the conventional Eu-complex. Therefore, we achieved the...

Thiophene substituted chalcones (1a-e) were cyclised with thiourea in presence of potassium hydroxide to get 4-substituted-6-(thiophen-2-yl)pyrimidine-2-thiols (2a-e) which were then stirred with methyl iodide to obtain 4-substituted-2-(methylsulfanyl)-6-(thiophen-2-yl)pyrimidines (3a-e). Compounds (3a-e) were refluxed with different N-methylpiperazine and N-phenylpiperazine to afford 4-substit...

Monodeuterated methanol is thought to form during the prestellar core stage of star formation. Observed variations in CH2DOH/CH3OD ratio suggest that its formation strongly dependent on surrounding cloud conditions. Thus, it a potential tracer physical conditions before onset A single-point model representative typical coupled chemical models investigate pathways toward deuterated at stage. Sim...

The requirement of many Brucella abortus strains for a PCO2 of approximately 0.03 atmosphere for growth seems to differ both quantitatively and qualitatively from the C02 requirement of other heterotrophic organisms. In some microorganisms, C02 can be replaced by certain tricarboxylic acids (Lwoff and Monod, 1946; Ajl and Werkman, 1948), amino acids (Lyman et al., 1947; Abelson et al., 1952a, b...

Deuterated chitosan was produced from the filamentous fungus Rhizopus oryzae, cultivated with deuterated glucose in H2O medium, without need for conventional chemical deacetylation. After extraction and purification, composition structure were determined by Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), small-angle neutron scattering (SANS). 13C NMR experiment...