little circle here between the nitrogen, the amino group and the carboxyl group. And the consequence...
and will act acidic when dissolved in water. Now our bodies can synthesize only ten of the twenty am...
Lecture Series on BioChemistry I by Prof.S.Dasgupta, Dept of Chemistry, IIT Kharagpur. For more deta...
antiparallel. The amino acid side chains from each strand alternately extend above and below the she...
Lecture Series on biochemistry I by Prof.S.Dasgupta, Dept of Chemistry, IIT Kharagpur. For more deta...
Lecture Series on biochemistry I by Prof.S.Dasgupta, Dept of Chemistry, IIT Kharagpur. For more deta...
amino acid side chains in the enzymes active site: glutamate 35 and aspartate 52. The highlighted gr...
, forming a five-membered ring that includes the backbone nitrogen. This geometry severely limits th...
Chemistry 3B: Chemical Structure and Reactivity. Spring 2006. Professor Peter Vollhardt. Chemistry 3...
Chemistry 3B: Chemical Structure and Reactivity. Spring 2006. Professor Peter Vollhardt. Chemistry 3...
thumbnail|300px|The general structure of an α-amino acid, w...
Structurally, local anesthetics consist of three molecular c...
2-Amino-1,2-dihydronapthalene (2-ADN), also known as 2-amino...
Amino Yoshihiko (; January 22, 1928–February 27, 2004) was...
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Abstract: Genetics Division, National Institute for Medical Research, London, UK.
Mild acid degradation of the lipopolysaccharide of the bacterium Idiomarina zobellii, type strain KMM 231T, with aq 2% HOAc at 100 degrees C, yielded an oligosaccharide, which represents one repeating unit of the O-polysaccharide. A polysaccharide was obtained by mild base degradation of the lipopolysaccharide. The following structure of the O-polysaccharide was elucidated by 1H and 13C NMR spectroscopy of the oligosaccharide and base-degraded lipopolysaccharide, including COSY, TOCSY, ROESY, 1H, 13C HSQC, HSQC-TOCSY and HMBC experiments: [-->3...
Novel amino-pyrazolone, amino-isoxazolone and amino-pyrimidinone derivatives were prepared from ethyl 4-phenylsulfonyl-2-(2'-phenylsulfonylethyl)-2-cyanobutyrate (1), ethyl 4-arylsulfonyl-3-aryl-2-cyanobutyrate (7) and ethyl 4-arylmethylsulfonyl-3-aryl-2-cyanobutyrate (8). The lead molecules have been tested for their antimicrobial activity and antioxidant property.
Density functional theory (DFT) and Monte Carlo (MC) simulation with free energy perturbation (FEP) techniques have been used to study the tautomeric proton transfer reaction of 2-amino-2-oxazoline, 2-amino-2-thiazoline, and 2-amino-2-imidazoline in the gas phase and in water. Two reaction pathways were considered: the direct and water-assisted transfers. The optimized structures and thermodynamic properties of stationary points for the title reaction system in the gas phase were calculated at the B3LYP/6-311+G(d, p) level of theory. The potent...
1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induces parkinsonism in humans after its oxidation into 1-methyl-4-phenylpyridinium ion (MPP+) by type B monoamine oxidase. The 1-amino analogues of MPTP and MPP+, 1-amino-4-phenyl-1,2,3, 6-tetrahydropyridine (APTP) and 1-amino-4-phenylpyridinium ion (APP+), were synthesized, and their cytotoxicity to clonal pheochromocytoma PC12 cells was examined using a tetrazolium formazan assay. After incubation for 48 and 72 h, both APP+ and APTP were found to be cytotoxic to PC12 cells, whereas with the...
As the second part of our studies on the impurity profiles of amino acids produced by biotechnological processes, a micellar electrokinetic chromatography (MEKC) was applied to determine amino sugars, low molecular peptides and amino acids as potential expected impurities at a level 0.1% w/w. 3-(4-Carboxybenzoyl)quinoline-2-carboxaldehyde (CBQCA) was found to be suitable as a labeling reagent for laser induced fluorescence (LIF) detection. The labeling reaction was optimized to achieve maximum reaction yields and reproducibility for all groups ...
Colon tumors were induced in F344 rats by three heterocyclic amines (HCAs), 2-amino-6-methyl-dipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) or 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), and examined for p53 mutations. Seven carcinomas induced by Glu-P-1, and nine carcinomas and two adenomas induced by IQ were examined by cDNA-polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis from codon 103 to 391 of p53, which encompasses the conserved regions II to IV. N...
The metabolic processing and disposition of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), three heterocyclic amine mutagens and carcinogens derived from cooked food, was examined in cynomolgus monkeys. IQ is an established hepatocarcinogen in cynomolgus monkeys; however, the carcinogenicity of MeIQx and PhIP is not yet known. IQ was extensively metabolized with little parent compound excreted in urine. Urinary metabolites of IQ ari...
A gas chromatographic-mass spectrometric assay has been developed for the measurement of 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (DiMeIQx) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in food. Stable isotope-labelled analogues of MeIQx and PhIP are used as internal standards and the synthesis of deuterated PhIP is described. The mass spectrometer is operated in the electron-capture negative ion chemical ionisation mode and the amines are chromatographed as their di-3,...
In the crystal structures of the title compounds, C(6)H(10)N(3)O(2)+.C(7)H(5)O(3)-.H2O, (I), C(6)H(10)N(3)O(2)+.C(7)H(4)NO(4)-.H2O, (II), and C(6)H(10)N(3)O(2)+.C(4)H(5)O(6)-.C(6)H(9)N(3)O(2), (III), the 2-amino-4,6-dimethoxypyrimidinium cation [abbreviated as (MeO)2-Hampy+] interacts with the carboxylate group of the corresponding anion through a pair of nearly parallel N-H...O hydrogen bonds to form R(2)(2)(8) ring motifs. In (I), the (MeO)2-Hampy+ cation is centrosymmetrically paired through a pair of N-H...N hydrogen bonds involving the 2-a...