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571.
Dong-Young Kum Mohamad Nazari Kerry L. McPhail Christina S. Cooper Takashi L. Suyama 《Tetrahedron letters》2017,58(34):3374-3376
A marine natural product isolated from Pseudoalteromonas sp., pentabromopseudilin, with promising anti-MRSA and myosin ATPase inhibition activities was synthesized in two steps using recently developed MIDA boronate Suzuki-Miyaura coupling technology. Additionally, bromination was shown to be necessary for the antimicrobial activity of pentabromopseudilin. 相似文献
572.
Buyng Su Hwang Yong Tae Jeong Sangbum Lee Eun Ju Jeong Jung-Rae Rho 《Molecules (Basel, Switzerland)》2021,26(11)
Densazalin, a polycyclic alkaloid, was isolated from the marine sponge Haliclona densaspicula collected in Korea. The complete structure of the compound was determined by spectroscopic methods, including 1D and 2D nuclear magnetic resonance techniques, high-resolution mass spectrometry, and comparison of the calculated and measured electronic circular dichroism spectra. Densazalin possesses a unique 5,11-diazatricyclo[7.3.1.02,7]tridecan-2,4,6-triene moiety, which is connected by two linear carbon chains. This compound was derived from the biogenetic precursor bis-1,3-dialkylpyridnium. Densazalin exhibited cytotoxic activity on two human tumor cell lines (AGS and HepG2) in the Cell Counting Kit-8 (CCK-8) bioassay, with IC50 values ranging from 15.5 to 18.4 μM. 相似文献
573.
Hong-Ying Niu Ling-Yun Su Shi-Xia Bai Jian-Ping Li Xi-Lan Feng Hai-Ming Guo 《中国化学快报》2017,28(1):105-108
C8-Alkyl-substituted purine analogues were synthesized through direct alkylation of 8-H purine with tetrahydrofuran in the presence of Co catalyst in one step. The reactions gave a series of novel C8-oxygen heterocyclic alkyl purine compounds in good yields under mild reaction conditions by the readily available alkylating reagents, providing a complementary route to the classical coupling reactions for the synthesis of C8-alkyl-substituted purine analogues. 相似文献
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Si-Si Zhu Yi-Fan Zhang Meng Ding Ke-Wu Zeng Peng-Fei Tu Yong Jiang 《Molecules (Basel, Switzerland)》2022,27(6)
Clausena lenis Drake (C. lenis) is a folk medicinal herb to treat influenza, colds, bronchitis, and malaria. The 95% and 50% ethanol extract of C. lenis showed significant nitric oxide (NO) inhibition activity in BV-2 microglial cells stimulated by lipopolysaccharide (LPS). Bio-guided isolation of the active extract afforded five new compounds, including a chlorine-containing furoquinoline racemate, (±)-claulenine A (1), an amide alkaloid, claulenine B (2), a prenylated coumarin, claulenin A (3), a furocoumarin glucoside, clauleside A (4), and a multi-prenylated p-hydroxybenzaldehyde, claulenin B (5), along with 33 known ones. Their structures were determined via spectroscopic methods, and the absolute configurations of new compounds were assigned via the electronic circular dichroism (ECD) calculations and single-crystal X-ray diffraction analysis. Compounds 2, 23, 27, 28, 33, and 34 showed potent anti-neuroinflammatory effects on LPS-induced NO production in BV-2 microglial cells, with IC50 values in the range of 17.6–40.9 μM. The possible mechanism was deduced to interact with iNOS through molecular docking. 相似文献
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Two new alkaloids, N-allylnitrarine and komarovidinine N-oxide were isolated from the aerial part ofNitraria komarovii.Their structures were established by chemical transformations and spectral data. 相似文献
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