Industrial electrosynthesis of organics in Europe is comprehensively treated. The products are divided in ten classes. Besides the adiponitrile process in UK, the sebacic acid process in USSR and the benzaldehyde process in Germany, scaled up to at least 1, 000 tons per year, numerous small capacity processes are described. Undivided cells are employed with increasing tendency.

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Psoralens are one isomeric form of furocoumarins whose photochemical reactivity toward DNA has long been used in the treatment of skin disorders such as psoriasis and vitiligo. Upon irradiation, consecutive addition reactions at the two reactive sites of a psoralen molecule toward two thymine residues of different strands of DNA result in the cross-linking of DNA, which is one of the most important outcomes for the therapeutic effectiveness of psoralen. However, this cross-linking is also considered mainly responsible for some undesired side effects such as skin cancer. Therefore, one of the important lines of current research in the field of psoralen photochemotherapy consists of developing effective monofunctional furocoumarins capable of modifying DNA without cross-linking two strands.
Interestingly, the site-selectivity (chemoselectivity) of two reactive sites in a photo-excited psoralen in DNA is different from that in solution. Such a remarkable difference in the site-selectivity in different environments strongly indicates an important role of intercalation into DNA in controlling psoralen's site selectivity. In this article, through the analysis of the nature of this intercalation step, several ideas are presented to develop new and more effective monofunctional molecules that would photochemically modify DNA. This approach should provide us a better basis for understanding the psoralen's photochemotherapy and developing medicinally as well as chemically useful furocoumarins and the related compounds.

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In this article are described the synthetic studies on two types of “oligosaccharins”, oligosaccharides from both fungal and plant origins, that elicit phytoalexin accumulation in soybean.
Two research groups have synthesized oligosaccharides related to β-glucan elicitor derived from pathogenic fungal cell wall.
Biological examination of the chemically synthesized oligo-β-glucosides revealed that minimum structure required for the elicitor activity is β-D-glucohexaoside, and that the branched trisaccharide at nonreducing end of the oligoglucosides is essential for maximum elicitor activity.
α- (1→4) -Linked oligogalacturonic acids (d.p. 10-13) derived from plant cell wall pectic polysaccharides are the “endogeneous elicitors” of phytoalexin accumulation in soybean.
Total synthesis of dodecagalacturonic acid was achieved by way of highly stereoselective glycosylation that involved glycosyl fluorides as the donors and oxidation of the twelve primary hydroxy groups in the α- (1→4) -linked galactododecaoside derivative. The synthetic dodecagalacturonic acid was active as an elicitor of soybean phytoalexin and was synergistic with the hepta-β-glucoside elicitor.

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The log P value used for the hydrophobicity parameter, where P is the partition coefficient in a 1-octanol/pH 7.0 buffer system, of a number of di-pentapeptides was analyzed with physicochemical parameters for the side chain substituent of component amino acids. The log P value was shown to be governed not only by the “intrinsic” hydrophobicity but also by the steric effect of side chain substituents as well as intramolecular-type solvation and “polar proximity” effects for polar side chains. The β-turn conformational parameters of component amino acids devised from the Chou-Fasman propensity index were nicely applied for the analysis of log P value of tetra-and pentapeptides.Using the results of the correlation analyses for log P of oligopeptides, we proposed a new effective hydrophobicity scale, π_α, for unionizable amino acid side chains. This scale and the hydrophobicity of oligopeptides would be useful not only for the process of peptide synthesis but also for the quantitative analysis of the structure-activity relationship of bioactive peptides.

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Cell-surface complex carbohydrates as glycoconjugates mediate cell-to-cell communication, cell-cell recognition and the “social behavior” of cells. Glycosidases and glycosyltransferases are responsible for the control of these functions by the metabolism of cell-surface carbohydrates. On the one hand the inhibitors of these enzymes contribute to the investigations of several important biochemical processes through the better understanding of the mechanism of action of these enzymes, while on the other hand they are of pharmaceutical interest in the treatment of metabolic diseases associated with changes in the levels of these enzymes, or caused by these enzymes from other species.
The present article discusses the progress in the synthesis, biochemistry and pharmacology of the natural glycosidase inhibitors with the structural relationship to carbohydrates.

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CH₂=CH-_??_N

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