13100-82-8

(Chemical Equation Presented) Neopetrosiamdes A (1) and B (2), two diastereomeric tricyclic peptides that inhibit amoeboid invasion of human tumor cells, have been isolated from the marine sponge Neopetrosia sp. collected in Papua New Guinea. The structures of the neopetrosiamides were elucidated by analysis of MS and NMR data and confirmed by chemical degradation.

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A kinetic spectrophotometric method based on the initial rate measurement has been developed for the determination of N-acetyl L-cysteine. The developed method is based on the oxidation of N-acetyl L-cysteine with iodate. The reaction product was studied and characterized using the mass spectrometry and the structure of the product was proposed. From the mass spectrometric studies it was concluded that the oxidation of the drug resulted in the formation of a disulfide. The developed method was validated as per the guidelines of international conference on harmonization. The developed initial rate method was found to be linear in the concentration range of 1.25-30 μg ml-1. The detection and quantitation limits were found to be 0.018 and 0.056 μg ml-1. In the current study, the degradation product of N-acetyl L cysteine was also prepared and identified using mass spectrometry.

Modified glucagon peptides are disclosed having improved solubility while retaining glucagon agonist activity. The glycogen peptides have been modified by substitution of native amino acids with, and/or addition of, charged amino acids to the carboxy terminus of the peptide. The modified glucagon agonists can be further modified by pegylation, or the addition of a carboxy terminal peptide selected from the group consisting of SEQ ID NO: 20, SEQ ID NO: 21, SEQ ID NO: 23, or both to further enhance the solubility of the glucagon agonist analogs.

Modified glucagon peptides are disclosed having enhanced potency at the glucagon receptor relative to native glucagon. Further modification of the glucagon peptides by forming lactam bridges or the substitution of the terminal carboxylic acid with an amide group produces peptides exhibiting glucagon/GLP-1 receptor co-agonist activity. The solubility and stability of these high potency glucagon analogs can be further improved by modification of the polypeptides by pegylation, substitution of carboxy terminal amino acids, or the addition of a carboxy terminal peptide selected from the group consisting of SEQ ID NO: 26 (GPSSGAPPPS), SEQ ID NO: 27 (K-RNRNNIA) and SEQ ID NO: 28 (KRNR).

There are provided nucleic acids, including isolated DNA molecules, which encode glutamate 2,3-aminomutase enzymes, polypeptides produced from such nucleic acids and methods of making the nucleic acids and polypeptides. There are further provided methods of producing β-glutamate from glutamate using glutamate 2,3-aminomutase.

Purpose. Peroxide impurities play a critical role in drug oxidation. In metal-free aqueous solutions, hydrogen peroxide (H2O2) induced thiol oxidation involves a bimolecular nucleophilic reaction to form a reactive sulfenic acid intermediate (RSOH), which reacts with a second thiol to form a disulfide (RSSR). This study examines the reaction of cysteine (CSH) and H2O2 in amorphous polyvinylpyrrolidone (PVP) lyophiles to explore the possible relevance of the solution mechanism to reactivity in an amorphous glass. Materials and Methods. Amorphous PVP lyophiles containing CSH and H2O2 at varying initial 'pH' and reactant concentrations were prepared by methods designed to minimize reaction during lyophilization. Kinetic studies were conducted anaerobically at 25°C and reactants and products were monitored by HPLC. Products were characterized and the kinetic data were fit to models adapted from the solution mechanism. Results. Key differences in the reactions in aqueous solution and amorphous PVP are: (1) while only cystine (CSSC) forms in solution, three degradants-cysteine sulfinic acid (CSO2H), cysteine sulfonic acid (CSO3H) and cystine (CSSC)-form in amorphous PVP; (2) simple bimolecular kinetics govern the solution reaction while initial rates in amorphous PVP suggested more complex kinetics (i.e., non-unity values for reaction order); and (3) heterogeneous (i.e., biphasic) reaction dynamics are evident in amorphous PVP. The differences in product formation and apparent reaction orders in the solid-state could be rationalized by partitioning of the same reactive intermediate to multiple products in the solid-state due to the restricted mobility of CSH. Beyond the initial rate region, the kinetics in amorphous PVP could be described by the Kohlrausch-Williams-Watts (KWW) stretched-exponential equation or by assuming two populations of reactant molecules having different reactivities. Conclusions. When reactive intermediates are involved, differences in degradant profiles and other characteristics (e.g., rate constants, apparent reaction order) in the amorphous-state may simply reflect altered rates for individual reaction steps due to glass-induced changes in relative reactant mobilities rather than a change in overall mechanism.

There is provided a fluorescent adduct which is amenable to detection by fluorometric and electrochemical techniques. The adduct is of the formula: STR1 wherein X is a radical derived from a primary amine of the formula X--NH2 and where R1 --R6 are selected from various organic or inorganic substituents.

A polymer-supported persulfonic acid has been prepared and applied for the oxidation of carboxylic acids, ketones, olefins, and disulfide bonds of cystine and cystinyl peptides to their peracids, esters (lactones), epoxides and sulfonic acid derivatives respectively in good yields.The resin also effectively removed the formyl protection from formyl amino acids.Spent polymer was reactivated by simple reactions.

A preparation containing an absorption promoter selected from specific classes of water-soluble macromolecular compounds having chelating activity, preferably in the presence of a salt at a concentration such that the composition exhibits higher osmotic pressure than isotonic sodium chloride solution, and a medicine is found to promote absorption of the medicine through a gastrointestinal organ such as the colon, rectum, or vagina.

It was found that Argon arc plasma induced a powerful and clean stepwise oxidation reaction in aqueous solution containing various amino acids without using any oxidizing agent.