Phosphotungstic acid (which will be designated as PTA) has long been used in separations of the amino acids. It was employed by Drechsel (1) in the discovery of lysine in casein, and by Hausmann (2), by Osborne, Leavenworth, and Brautlecht (3), and by Van Slyke (4-8) for quantitative precipitation of the diamino acids, arginine, lysine, and histidine, in protein hydrolysates. Cystine was found ...

The asymmetric unit of the title compound, 2C(5)H(8)N(3) (+)·2C(2)HO(4) (-)·H(2)O, contains two crystallographically independent 2,6-diamino-pyridinium cations, a pair of hydrogen oxalate anions and a water mol-ecule. Both 2,6-diamino-pyridinium cations are planar, with maximum deviations of 0.011 (2) and 0.015 (1) Å, and are protonated at the pyridine N atoms. The hydrogen oxalate anions adopt...

 In this article, synthesis of the explosive 2, 6 (diamino) 3, 5 dinitro pyridine (ANPY) of the direct nitration reaction of 2, 6 diamino pyridine in different conditions of temperature, with density functional theory method were studied. For this purpose, at first the material contained in the both sides of reaction were geometrically optimized, then the calculation of the the...

The presence of a remarkably high concentration of pteridiineS in the blue green alga, Anacystis nidulanis 5, wvas demonstrated by Forrest, van Baalen, and Myers in 1957 (2). A number of (lifferent pteridines were then isolated and ideentifie(l. These included 2-amino-4-hydroxypteridine, 2,6-diamino-4-hydroxypteridline (10), a yellow pteridine assigned the structure 2-aimino-4-hydroxv-6-propion...

The synthesis of stable guanofosfocin analogues has attracted considerable attention in the past 15 years. Several guanofosfocin analogues mimicking the three constitutional elements of mannose, ribose, and guanine were designed and synthesized. Interest in ether-linked pseudodisaccharides and 8-alkylated guanines is increasing, due to their potential applications in life science. In this artic...

Some new nitrogen bridge-head pyrido[1,2-b][1,2,4]triazepines incorporating 6methylchromone moiety have been synthesized from the reaction of 1,6-diamino-4-(6methyl-4-oxo-4H-chromen-3-yl)-2-oxo-1,2-dihydropyridine-3,5-dicarbonitrile (4) with some α,γ-bifunctional electrophiles including 2-cyano-3,3-bis(methylthio)acrylonitrile, 2cyano-3,3-bis(methylthio)prop-2-enamide, 5-chloro-3-methyl-1-pheny...

Molecular mechanisms underlying diabetes-induced painful neuropathy are poorly understood. We have demonstrated, in rats with streptozotocin-induced diabetes, that mechanical hyperalgesia, a common symptom of diabetic neuropathy, was correlated with an early increase in extracellular signal-regulated protein kinase (ERK), p38, and c-Jun N-terminal kinase (JNK) phosphorylation in the spinal cord...