Red light as a 12-oxo-leukotriene B₄ antagonist: an explanation for the efficacy of intensive red light in the therapy of peripheral inflammatory diseases.

To explain the successful treatment of various inflammatory diseases by using intensive red light, a non-linear theory is presented for the interaction of electric dipoles with light involving frequency doubling. It is applied to analyze the influence of light on organic molecules with permanent electric dipoles. The molecule 5-hydroxy-12-oxo-(5S,6Z,8E,10E,14Z)-6,8,10,14-eicosatetraenoic acid, 12-oxo-leukotriene B4 (12-Oxo-LTB4, an intermediate in the lipoxygenase-catalyzed path of arachidonic acid metabolism), is suspected to play a major role in the healing process, as, first, it plays a key role in the metabolism of leukotriene B4 (LTB4), which in many diseases acts as a source of inflammatory reactions; second, its dipole resonance is located at a wavelength of 316 nm, which can be excited by a 632 nm source through frequency doubling.

Structural analysis of an impurity of the drug landiolol.

In a course of development and preparation of landiolol (1a), a known ultra-short-acting β-blocker, process quality control by HPLC and LC-MS analysis consistently showed an impurity peak ranging from 0.05% to 0.15 % and exhibiting a molecular mass m/z 887.

NXO building blocks for backbone modification of peptides and preparation of pseudopeptides.

The design and synthesis of novel building blocks for peptide modification, termed "NXO", is reported. We describe the utility of these building blocks to prepare new pseudo- and oligopeptides and demonstrate the efficient assembly of modified tripeptides using both conventional liquid phase peptide synthesis and solid supported synthesis. Pertaining to the study of NXO in peptide mimicry, the structure of NXO-incorporating tripeptide beta-strand mimics was investigated in the N(L)AlaO incorporating beta-sheet model compound 13.