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91.
Atsuyoshi Nakayama Naoko Yamano Norioki Kawasaki Yasuhide Nakayama 《Polymer Degradation and Stability》2013
Copolyesteramides of 2-pyrrolidone with ε-caprolactone were synthesized by ring-opening copolymerization. The copolymers were random-like and their melting temperature and heat of fusion were dependent on the polymer composition. Biodegradation by a polyamide 4 (PA4) degrading microorganism showed rapid degradation in the region of amide-rich polymer composition. On the contrary, enzymatic hydrolysis using a lipase resulted in a different tendency, that is, ester-rich copolymers hydrolyzed rapidly. Activated sludge makes copolymers degrade to CO2 in wide polymer composition ratio. Copolyesteramides are expected to be applied as an environmentally-friendly plastics or bioabsorbable polymers in medical fields. 相似文献
92.
Novel 2-iminiomethylvinamidinium trihalides were isolated as stable crystals and found to be useful triformylmethane synthons with non-deliquescent nature in air. They were easier to manufacture, handle, and store than the known 2-iminiomethylvinamidinium dichloride. By virtue of in situ aminal protection, a combination of the vinamidinium salt with a secondary amine achieved an efficient and scalable synthesis of 7-acylamino-3-formylquinoline, a versatile synthetic intermediate for potent anti-obesity drugs 7-acylamino-3-aminomethyl-8-methylquinolines. 相似文献
93.
94.
3-Acetyltropolone ( 1 ) reacted with aminoguanidine to afford its guanylhydrazone ( 3 ). The reaction of 3-acetyl-2-methoxytropone ( 2a ) gave 4-methyl-1(2H)-phthalazinone ( 5 ), while the reaction of 7-acetyl-2-methoxytropone ( 2b ) gave its guanylhydrazone ( 6 ) and 3-methyl-1,8-dihydrocycloheptapyrazol-8-one ( 4 ). The guanylhydrazones ( 3 and 6 ) were easily cyclized to 4 by heating in acetic acid. 相似文献
95.
Optical Review - Two-point resolution for ordinary microscopy was studied in a bright background under partially coherent light. The basic equation was derived from the unified theory of image... 相似文献
96.
Jin‐Jun Wang Young Key Shim Gui‐Ji Jiang Kimiaki Imafuku 《Journal of heterocyclic chemistry》2003,40(6):1075-1079
Methyl pyropheophorbide‐a (MPPa) ( 1 ) was converted to two aldehydes, methyl 2‐formylmethyl‐2‐devinylpyropheophorbide‐a ( 2 ) and methyl 2‐formyl‐2‐devinylpyropheophorbide‐a ( 3 ). The former 2 reacted with active methylene compounds having a cyano function in the presence of sulfur to afford thiophene‐substituted chlorins 5a‐c and reacted with arylhydrazines to yield indole‐substituted chlorins 6a‐d . From the latter 3 , a α‐diketo chlorin 7 was obtained via Wittig reaction and oxidation. Compound 7 reacted with o‐phenylenediamine to afford 2‐quinoxalyl‐substituted pyropheophorbide‐a 8. The reaction of MPPa ( 1 ) with anthranilamide to give a spiro‐substituted compound 9 . 相似文献
97.
1-Cyano-2-N,N-dimethylformamidinylazulenes as new synthons directed to heterocycle-fused azulenes were obtained by the condensation of 2-amino-1-cyanoazulenes and N,N-dimethylformamide dimethyl acetal (DMFDMA). 1-Cyano-2-N,N-dimethylformamidinylazulene (2a) and 1-bromo-3-cyano-2-N,N-dimethylformamidinylazulene (2b) reacted with anilines (3a–h) to give 4-N-arylaminoazuleno-[2,1-d]pyrimidines in moderate yields. This reaction provides a new procedure for synthesis of pyrimidine-fused azulenes. 相似文献
98.
Stereoselective total synthesis of the C(40)-diacetylenic carotenoid alloxanthin (1) and the C(31)-acetylenic apocarotenoid triophaxanthin (2) was accomplished by Wittig condensation of C(10)-dialdehyde 20 or C(16)-keto aldehyde 19, respectively, with C(15)-acetylenic tri-n-butylphosphonium salt 12. 相似文献
99.
Thiazole derivatives have attracted a great deal of interest owing to their physiological activities. In addition, thiazoles are also useful in dye and photographic industry.[1] In the present paper we report the synthesis of azulenes containing a thiazole moiety. 相似文献
100.
Okada K Beppu S Tanaka K Kuratsu M Furuichi K Kozaki M Suzuki S Shiomi D Sato K Takui T Kitagawa Y Yamaguchi K 《Chemical communications (Cambridge, England)》2007,(24):2485-2487
A new one-dimensional chain complex, Mn(hfac)(2)-bridged [2-(3-pyridyl)(nitronyl nitroxide)Mn(hfac)(2)](2), was prepared and its structure and magnetic properties were elucidated; the complex exhibited a large antiferromagnetic interaction of J(1)=-185 K between the three Mn(ii) atoms and the two nitronyl nitroxides to give S=13/2 spin units and a small ferromagnetic interaction of J(3)'=+0.02 K between these spin units at low temperatures (50-1.9 K), compatible with the theoretical analysis for model compounds. 相似文献