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61.
Antitumor effect of pluronic F-127 gel containing mitomycin C on sarcoma-180 ascites tumor in mice. 总被引:5,自引:0,他引:5
Pluronic F-127 (PLF-127) gels were evaluated as a sustained-release vehicle for intraperitoneal administration of mitomycin C (MMC) in order to enhance the therapeutic effects of MMC against a Sarcoma-180 ascites tumor in mice. Tumor cell injections were made on day 0 and injections of MMC in 25% (w/w) PLF-127 on day 1, both intraperitoneally. A prolongation of the life span of tumor-bearing mice following injection of therapeutic PLF-127 was noted, and PLF-127 containing MMC was therapeutically more active than free drug. The high chemotherapeutic efficiency of MMC in PLF-127 was striking at high doses, which would be toxic in the case of the drug alone. PLF-127 gels exhibit reverse thermal behavior and are fluid at refrigerator temperature, but are soft gels at body temperature. The in vitro release experiments indicated that Pluronic gel might serve as a rate-controlling barrier and be useful as a vehicle for sustained-release preparations of MMC to be administered intraperitoneally. These results suggest that sustained-release occurs in the peritoneum and that effective drug concentrations can be maintained by the preparation. 相似文献
62.
Rapid and Efficient Copper‐Catalyzed Finkelstein Reaction of (Hetero)Aromatics under Continuous‐Flow Conditions 下载免费PDF全文
Dr. Mao Chen Saki Ichikawa Prof. Dr. Stephen L. Buchwald 《Angewandte Chemie (International ed. in English)》2015,54(1):263-266
A general, rapid, and efficient method for the copper‐catalyzed Finkelstein reaction of (hetero)aromatics has been developed using continuous flow to generate a variety of aryl iodides. The described method can tolerate a broad spectrum of functional groups, including N‐H and O‐H groups. Additionally, in lieu of isolation, the aryl iodide solutions were used in two distinct multistep continuous‐flow processes (amidation and Mg–I exchange/nucleophilic addition) to demonstrate the flexibility of this method. 相似文献
63.
Dr. Akihiro Takada Hiroaki Fujiwara Dr. Kenji Sugimoto Dr. Hirofumi Ueda Prof. Dr. Hidetoshi Tokuyama 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(46):16400-16403
The total synthesis of (?)‐isoschizogamine was accomplished, featuring the construction of the quaternary carbon center by the modified Johnson–Claisen rearrangement in basic media and the facile assembly of the key tetracyclic quinolone intermediate through a cascade cyclization. The characteristic cyclic aminal was constructed by late‐stage C?H functionalization at the position adjacent to the lactam nitrogen using a combination of CrO3 and nBu4NIO4 and subsequent Bi(OTf)3‐mediated cyclization. 相似文献
64.
Efficient and stereoselective synthesis of a disaccharide fragment, 2-deoxy-4-O-(N'-monodemethyl-D-forosaminyl)-2-methylamino-β-D-xylopyranoside, of a novel antibiotic, incednine (1), is described. The key β-stereoselective formation of a 2,3,4,6-tetradeoxy-4-methylamino glycoside bond was achieved by remote participation-assisted glycosylation. 相似文献
65.
Two new vanadotellurates, [HTeV(9)O(28)](4-) and [H(2)TeV(9)O(28)](3-) have been synthesized and structurally characterized as tetra-n-butylammonium (TBA) salts: TBA(4)[HTeV(9)O(28)]·2CH(3)CN [triclinic, space group P ?1, a = 16.7102(6) ?, b = 17.4680(7) ?, c = 17.9634(7) ?, α = 74.412(1)°, β = 67.494(1)°, γ = 74.160(2)°, Z = 2] and TBA(3)[H(2)TeV(9)O(28)] [monoclinic, space group P2(1)/c, a = 13.0013(5) ?, b = 19.157(1) ?, c = 28.453(1) ?, β = 97.222(2)°, Z = 4]. The results of the structural analyses indicate that the four O atoms that bridge two V atoms on the Te side are the most basic ones in the structure. The results of density-functional theory (DFT) calculations support this view. 相似文献
66.
K. Sasaki O. Takahashi N. Takada M. Nagatsu T. Tsukishima T. Okada S. Okajima Y. Tsunawaki S. Sudo K. N. Sato et al. 《International Journal of Infrared and Millimeter Waves》1995,16(12):2133-2146
Spectrally narrow, pulsed outputs consisting of almost a single mode have been obtained from an optically-pumped high-power (200kW) D2O laser by adopting the injection seeding method, where single-mode radiation (seed pulse) from a low-power, compact D2O laser has been injected into the main D2O laser. Spectrally narrow outputs with high power having spectral widths as narrow as 5 MHz have been obtained, when the seed pulses with frequency tuned to one longitudinal mode of the main D2O laser have been injected at a time sufficiently before the lasing of the main laser took place. The experimental results have been compared with those of numerical simulation modified to include the injection field with varying injection times. 相似文献
67.
Yoshimi Yamaguchi Yoshihisa Okamoto Atsushi Takada 《Journal of heterocyclic chemistry》1997,34(6):1737-1739
A novel method for synthesis of a chiral amine borane is described and selective reductions of carbonyl compounds with the amine borane are investigated. 相似文献
68.
Neslihan Saki Engin U. Akkaya 《Journal of inclusion phenomena and macrocyclic chemistry》2005,53(3):269-273
A novel dimeric calixpyrrole has been synthesized. The dimer forms stable complexes with p-nitrophenolate ion with a concomitant reduction in extinction coefficient. The chromogenic anion is displaced by the addition of various anions like fluoride and acetate. Effective optical sensing of these anions is accomplished using the calixpyrrole dimer. 相似文献
69.
70.
K. Umeda T. Yamaya T. Suehiro K. Takimoto R. Wada E. Takada S. Shimoura A. Sakaguchi S. Murakami M. Fukada Y. Okuma 《Nuclear Physics A》1984,429(1):88-104
The differential cross sections for the (d, 6Li) reaction on targets of 12C, 16O, 24Mg, 40Ca, 58Ni and 94Mo have been measured at Ed = 54.2 MeV. The measured angular distributions have been analyzed by finite-range DWBA calculations, and spectroscopic factors for an α-cluster transfer have been extracted. In the DWBA analysis using an optical model with a phenomenological Woods-Saxon potential, the spin-orbit part of the deuteron optical potential played a significant role in reproducing the measured angular distributions but the spin-orbit part of the 6Li optical potential had a minor effect. Relative spectroscopic factors extracted from the present data were compared with theoretical predictions together with the results from the (p, pα) reaction. The relative spectroscopic factors for 1p-shell nuclei were in quantitative agreement with theoretical predictions. However, there were certain discrepancies between the spectroscopic factors extracted from the (d, 6Li) reaction and those from the (p, pα) reaction, and the discrepancies increased with target mass number. 相似文献