No abstract

An unprecedented Ru(II) catalyzed ortho-hydroxylation has been developed for the facile synthesis of a variety of multifunctionalized arenes from easily accessible ethyl benzoates with ester as an efficient directing group. Both the TFA/TFAA cosolvent system and oxidants serve as the critical success factors in this transformation. The reaction demonstrates excellent reactivity, good functional group tolerance, and high yields.

In the search for a new Cys side-chain protecting group that is compatible to the solid-phase peptide synthesis yet can be removed under mild conditions, the Hqm and Hgm groups that are readily deprotected by using aqueous hydrazine have been developed. The utility of these groups for peptide and protein chemistry is tested by the total synthesis of a peptide antibiotic trifolitoxin and the human neutrophil defensin hNP2.

A novel set of descriptors G-scale was derived from 457 physicochemical properties of the natural amino acids. The descriptors were then applied to study on quantitative structure-activity relationships (QSARs) of nine peptide datasets of angiotensin-converting enzyme inhibitor (ACE-inhibitor) oligopeptides (between dipeptides and decapeptides) by using partial least square (PLS) regression. The multiple correlation coefficients (R²) and leave one out cross validation values (Q²) of PLS models are better than or close to the results of references. The results show that the descriptors proposed here may be a useful structural expression method, and they may be hopefully used in biological activity study of ACE-inhibitor oligopeptides.