Highly fluorinated epoxides were polymerized under mild conditions regioregularly, which gave easy access to isotactic polymers by using optically pure epoxides.
1. Using adult Silkie and White Leghorn (WL) chickens, fibre composition and total collagen content were compared between M. iliolibialis lateralis (ITL) and M. pectoralis (PT). 2. Fibres were divided into type IIR and IIW showing strong and weak reduced nicotinamide adenine dinucleotide dehydrogenase activities, respectively. 3. Fibre composition differed markedly between ITL and PT muscle. ITL muscle was composed of both types IIR and IIW fibre but PT muscle of only type IIW Breed difference on composition was noted only in ITL muscle of cocks (type IIR; Silkie 53.8% and WL 37.0%). 4. Total collagen content was greater in ITL muscles and in cocks in both muscles. However, a breed difference was observed only in the PT muscle of hens. 5. In conclusion, the total collagen content was affected by muscle location within the body and by sex rather than by fibre composition.
Epoxides bearing fluorine (F)-containing substituents on ethylene oxide were polymerized under mild conditions to give regioregular polyethers. To alleviate the electron-withdrawing effect of fluoroalkyl or fluoroaryl groups, more than one unit of methylene spacer had to be introduced into a side chain for regioregular polymerization with high activity. Optically active isotactic polyethers were obtained from enatiopure monosubstituted ethylene oxides as a result of regioselective ring opening via successive cleavage of the less substituted carbon-oxygen bond. Obtained optically active isotactic polyethers were investigated through circular dichroism (CD) spectra or optical rotatory dispersion (ORD) spectra in solution states. As a result, no evidence for the formation of helical conformation was detected in both the F-substituted and the corresponding hydrogen (H)substituted optically active isotactic polyethers.
1. The collagen architecture of M. iliotibialis lateralis in chicken was observed under the scanning electron microscope after muscle maceration in NaOH. 2. Immunohistochemical methods showed Type I and III collagens to be distributed over both perimysium and endomysium. 3. Thick perimysium around secondary myofibre fasciculi was composed of many large longitudinal collagen bundles and a few small circumferential bundles. In contrast, thin perimysium around primary myofibre fasciculi showed mainly circumferential bundles. 4. Endomysium had a honeycomb-like structure and consisted of a fine collagen mesh, its main fibre striation being circumferential. 5. It is suggested that functional demand differs between thick perimysium and thin endomysium.
The scope and limitation of the ring-opening reaction of sulfonyl-activated aziridines using lithiated dithianes was investigated. Nucleophilic attack of lithiated dithianes on aziridines containing tert-butylsulfonyl (Bus) and 2-(trimethylsilyl)ethylsulfonyl (SES) demonstrated efficient ring cleavage to yield beta-amino carbonyl equivalents, gamma-lactam and syn- and anti-1,5-aminoalcohols. The first example of a ring-opening reaction of di-substituted aziridine using dithiane is also reported. Finally, the Bus and SES-possessing dithianes obtained were deprotected to demonstrate their synthetic usefulness.
Two kinds of thioether–trialkylphosphine ligands and their Rh complexes were synthesized and applied to the carbonylation of methanol to acetic acid to reveal that one of the two complexes showed higher activity compared to Rh catalyst without any ligands.
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