The ability for synthetic polymers to degrade in a controlled manner was developed for environmental reasons in the late 1960s. Interest in utilizing biodegradable polymers for biomedical applications rapidly followed and research focused on designing novel materials has continued to grow. Biodegradable polymers can be tailored for controlled degradation through numerous functional groups inclu...

Occupational asthma is important both as a potentially curable and preventable cause of asthma and as a model of adult onset asthma. It is induced by sensitization to a specific agent inhaled at work; for many of its causes, including inhaled proteins and the low molecular weight chemicals acid anhydrides and reactive dyes, it is probably IgE dependent. The risk of developing specific IgE and a...

We report on the synthesis of a series poly(ester-anhydride) composed following dicarboxylic acids: adipic, suberic, sebacic, dodecanedioic acids; and hydroxyalkanoic ricinoleic 12-hydroxystearic acid with control molecular weight approaching from new method in which well-defined ester monomers are first synthesized by stepwise addition acids molecules into melted acids. The key advantage this ...

For improving the hydrolytic stability of sulfonated polyimides consisting five membered anhydrides, novel (NSPIs) were prepared via polymerization 3,3?,4,4?-benzophenonetetracarboxylic dianhydride (BTDA), with a diamine monomer pendant sulfonic acid group and 4,4-oxydianiline. Water uptake this NSPI an excellent film-forming ability was almost equal to that Nafion® 117, while their ion exchang...

One-pot and facile preparations of 6-(2-hydroxy-5-R-benzoyl)-4-methyl-2-R1- pyrazolo[3,4-b]pyridines 4a-o are described, using the reaction of 3-formyl chromones 1 with 5-amino-1-R1-pyrazoles 2. An enamine-intermediate 2-ethyloxy-6-R-3-(3-methyl-1- phenylpyrazol-5-ylaminomethylene)chroman-4-one 3 was isolated at lower temperatures. Acyloxy-derivatives 5 of compounds 4 were obtained by acylation...

A regioselective synthesis has been developed for the preparation of a series of N,N'-disubstituted 4,4'-carbonylbis(carbamoylbenzoic) acids and N,N'-disubstituted bis(carbamoyl) terephthalic acids by treatment of 3,3',4,4'-benzophenonetetracarboxylic dianhydride (1) and 1,2,4,5-benzenetetracarboxylic dianhydride (2) with arylalkyl primary amines (A-N). The carbamoylcarboxylic acid derivatives ...

ante by carboxylic acid would result if the equilibrium of Reaction 3 were significantly toward R(CHz), CO-S-CoA or if the latter disappeared in secondary reactions. In practice, acetylCoA was incubated with enzyme fractions with and without added carboxylic acids under the conditions described in Table I. At the end of the incubation period, 0.1 volume of 30% metaphosphoric acid was added, the...