Contractile activity of porcine neuromedin U-25 and various neuromedin U-related peptide fragments on isolated chicken crop smooth muscle.

Contractile activity of porcine neuromedin U-25 (p-NMU-25) and various neuromedin U (NMU) peptide fragment amides was examined on chicken crop smooth muscle preparation. The relative activity (expressed as RA value) of p-NMU-25 to porcine neuromedin U-8 (p-NMU-8) was 5.51 +/- 0.09, and p-NMU-25 (15-25) was the most potent fragment with an RA value of 7.78 +/- 0.05. All C-terminal 11-peptide amides of rat, rabbit, and frog NMU peptides retained activity about three-fold higher than the corresponding C-terminal 8-peptide amides. The peptide segment Asn15-Arg-Arg17 of p-NMU-25, as well as the corresponding positions of various NMU peptides: Ser13-Gly-Gly15 of rat NMU and Ser15-Arg-Gly17 of rabbit and frog NMUs, appeared to be involved in the structural requirements for increased contractile activity in the assay system.     

Morphology and orientational disorder of C70 single crystals

C₇₀ single crystals, free from solvent contamination, were grown via vapor phase transport technique. The (0001) face of the C₇₀ crystal was imaged with Atomic Force Microscopy (AFM) under ambient atmosphere. Low-resolution images of a freshly prepared crystal revealed well-ordered faceted regions with multiple terraces extending over a region of several hundred square nanometers. The terraced structure in the images indicates that the crystals formed as a layer growth. In the high-resolution images, C₇₀ molecules were resolved in a hexagonal close packed (hcp) structure with an average center-to-center distance of 10.5±0.5 Å. After one month's exposure to the ambient atmosphere, the molecules rearranged into a mixed structure consisting of hcp and face centered cubic (fcc) regions.     

High-resolution preparative-scale gel-permeation chromatography

Sharp polymer fractions have been obtained in preparative-scale gel-permeation chromatography by use of a column set packed with polystyrene gel particles of about 10 μ diameter. When 0.13 g of standard polystyrene NBS 706 was fractionated per injection, fractions with polydispersities of about 1.02–1.03 were obtained over the molecular weight range 10⁴–10⁶. Effects of a injection volume, solution concentration, and fraction volume on fractionation efficiency were also investigated. Polydispersities of fractions increased appreciably with increasing amounts of polymer injected.     

New ochtodane syntheses from myrcene

The ochtodane skeleton is formed stereoselectively from myrcene via acid-catalyzed cyclization of the benzenesulfenyl chloride adduct and that epoxide in a biogenetic type fashion. Its application to the syntheses of two ochtodane-type monoterpenes, an aldehyde component of the boll weevil pheromone and a diol found in the red alga $\text{Ochtodes}$$\text{crockeri}$, is reported.     

Bioactive marine metabolites XII. Moritoside, an inhibitor of the development of starfish embryo, from the gorgonian sp.

Moritoside, a new hydroquinone glycoside which inhibits cell division of fertilized starfish eggs, has been isolated from the gorgonian sp.     

2-Alkoxycarbonylallyltrimethylsilanes as new reagents of 2-alkoxycarbonylallylation of electrophiles

2-Alkoxycarbonylallylsilanes are useful for 2-alkoxycarbonylallylation of acetals and carbonyl compounds with an aid of a Lewis acid; the products can be readily converted to α-methylene-γ-butyrolactones.