treatment of 1-(5-bromo-2-chloro-6-methylpyrimidin-4-yl)-1-methylhydrazine withdimethylthiocarbamoylchloride gave 7-chloro-n,n, 1,5-tetramethyl-1h-pyrimido[4,5-e][1,3,4]thiadiazin-3-amine in basic acetonitrile. the latter compounds were reacted withsecondary amines in boiling ethanol to afford the related 7-amino derivatives.

in this research, the characteristics of cmp dioxane lignin (hardwood origin) and soda bagasse lignin (ethanol soluble fraction) and dioxane lignin of bagasse were studied using gel permeation chromatography, gas chromatography-mass spectrometry and 13c nmr spectroscopy and dfrc degradation procedure. the results indicated that the main structural units in lignins are phenyl propane skeletons b...

Nonribosomal peptide synthetases (NRPSs) catalyze the biosynthesis of many biologically active peptides and typically are modular, with each extension module minimally consisting of a condensation, an adenylation, and a peptidyl carrier protein domain responsible for incorporation of an amino acid into the growing peptide chain. C-1027 is a chromoprotein antitumor antibiotic whose enediyne chro...

In order to increase the rate of gas absorption, chemical reaction in the liquid phase is considered. The purpose of this paper was to simulate gas absorption process by a liquid film over a spherical packing incorporating eddy viscosity and diffusivity. Second order chemical reaction for two different cases (fast and slow) were considered. The system partial differential equations obtained...

The nitrogen mustards used in these experiments were the hydrochlorides of ethyl bis (/3 chloroethyl) amine, methyl bis (/3 chloroethyl) amine, and tris (fl chloroethyI) amine. Sodium nucleate was prepared from calf thymus by a modification of Hammarsten's procedure (5). After the preliminary extraction, filtration, and addition of CaC12, a precipitate was obtained by bringing the final ethanol...

The reversible reaction of carbon dioxide (CO₂) with primary amines to form alkyl-ammonium carbamates is demonstrated in this work to reduce amine reactivity against nucleophilic substitution reactions with benzophenone and phenyl isocyanate. The reversible formation of carbamates has been recently exploited for a number of unique applications including the formation of reversible ionic liquids...

The title ZnII complex, [Zn(C18H18N3S)2], (I), features two independent but chemically equivalent mol-ecules in the asymmetric unit. In each, the thio-semicarbazonate monoanion coordinates the ZnII atom via the thiol-ate-S and imine-N atoms, with the resulting N2S2 donor set defining a distorted tetra-hedral geometry. The five-membered ZnSCN2 chelate rings adopt distinct conformations in each i...

production ofdimethyl amino ethanol (dmae) and effective parameters on efficiency and purity of the chemical were studied in this article. dimethylation of ethanol amine using aqueous formaldehyde in the presence of formic acid was applied for production of dmae. results showed that four parameters such as outlet temperature of co2 gas, reflux temperature, reflux time and extraction solvent wer...