Chemical Conversion of Cyclic .ALPHA.-Amino Acids to Cyclic .ALPHA.-Aminophosphonic Acids.

Acyclic to cyclic aminophosphonic and phosphinic acids

The results presented in this account deal with the synthesis of acyclic αor β-aminophosphonates or phosphinates and with the synthesis of heterocyclic compounds, where the phosphorus and/or the nitrogen atoms can be embedded in the heterocyclic core, showing new perspectives in bioactive molecules.

Antigenicity of Polypeptides (poly Alpha Amino Acids)

It has been shown that the polymers GLA5, GLT, GLA40, and GLAT are antigenic in human beings. Both immediate skin reactions and delayed (cellular) reactions were observed. The antibody produced reacted well in the precipitin reaction, agglutinated antigen coated tanned sheep cells, was less effective in inducing PCA reactions, and failed to sensitize guinea pigs for passive systemic anaphylaxis...

Alpha helix propensity of amino acids.

Synthesis and aromatisation of cyclic enediyne-containing amino acids.

A series of cyclic enediyne-containing amino acids with ring sizes varying from 10 to 12 atoms have been prepared starting from propargylglycine and homopropargylglycine. Their reactivity towards Bergman cyclisation under elevated temperatures has been explored. The enediynes displayed marked differences in cyclisation half-lives depending on the olefinic substituent and the ring size. A potent...

Physiological role of the cyclic hydroxamic acids

Roots of young seedleings of barnyard grass, maize, rye and wheat secret hydroxamic acids. Their compexes with Fe/III/-ions are available sources of iron. It is possible that the cyclic hydroxamic acids play a role in the alternative mechanism of iron uptake. The hydroxamic acids secreted by barnayard grass roots have an allelopathic role by inhibiting the roots growth of rice. Acta Biol Szeged...