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41.
New Diterpenoid Alkaloids from Spiraea japonica var. Ovalifolia 总被引:2,自引:0,他引:2
Guo Ying ZUO Hong Ping HE Xin HONG Wei Ming ZHU Yi Ming HU Xiao Sheng YANG Xiao Jiang HAO* Laboratory of Phytochemistry Kunming Institute of Botany Chinese Academy of Sciences Kunming Kunming Hospital PLA Kunming 《中国化学快报》2001,(2)
In the investigation of the chemical constituents of Spireae japonica L. f. var. ovalifolia (Rosaceae), a shrub originated in Songming, Yunnan, five new diterpenoid alkaloids, 19-O-deethylspiramine N (1), deacetylspiramine S (2), spiramidine A (3), spiramidine B (4) and deacetylspiramine F (5), were isolated from aerial parts of the plant and structurally elucidated. Compound 1, a white amorphous powder with [(]+17.99 (c, 0.26, MeOH ), was determined to have the molecular formula of C20H… 相似文献
42.
S. Suzgec L. Bitis S. Pirildar H. Ozcelik J. Zapp H. Becker F. Mericli A. H. Mericli 《Chemistry of Natural Compounds》2006,42(1):75-77
From the aerial parts of Delphinium schmalhausenii six norditerpenoid alkaloids gigactonine, lycoctonine, anthranoyllycoctonine, delsemine A, delsemine B, N-acetyldelectine and a diterpenoid alkaloid septatisine were isolated.
Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 60–61, January–February, 2006. 相似文献
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Hong-Ping Long Fu-Shuang Li Kang-Ping Xu Zhong-Bao Yang Jing Li Jun Peng Gui-Shan Tan 《中国化学快报》2014,25(5):805-808
Two new compounds named as 3b 12 16-trihydroxy-6 8 11 13-abietatrien(1) (8R 80S)-4 40 8-trihydroxyl-3 30-dimethoxyl-90-lignanolide(2) and a new natural product 4 40-dihydroxyl-3 30 5 50-dimethoxyldiphenyl diketone(3) were isolated from the whole herbs of Selaginella involven Spring.The structures were elucidated by spectroscopic analyses including UV,IR,1D,2D NMR and MS methods.Additionally,these three compounds exhibited potent protective effect against the injury of PC-12 cells induced by hypoxia/reoxygenation. 相似文献
45.
6β,7β,14β-Trihydroxy-1α-acetoxy-7α,20-epoxy-ent-kaur-16-en-15-one was isolated from the natural plant of Isodon japonica (Burm.f), Haravar. galaucocalyx (maxim) Hara. The structure was elucidated by means of spectral and chemical studies. In addition, its crystal was determined by single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P1, Z = 2, a = 6.3506(4), b = 13.5766(8), c = 15.2777(9) , α = 80.506(1), β = 83.856(1), γ = 88.307(1)o, C25H36O9, Mr = 480.54, V = 1291.64(13) 3, Z = 2, Dc = 1.236 g/cm3, F(000) = 516, μ = 0.093 mm-1, S = 0.988, the final R = 0.0761 and wR = 0.1955. Flack factor is 0.02(19), and the largest peak and deepest hole on the final difference Fourier map are 0.556 and –0.265 e/3, respectively. The X-ray diffraction shows the existence of intermolecular C–H…O (DA) hydrogen bonds between adjacent molecules. 相似文献
46.
The roots of Euphorbia fischeriana have been used as a traditional Chinese medicine for the treatment of tuberculosis and ringworm. In the current study, diterpenoids from the ethyl acetate extract of the roots E. fischeriana and their cytotoxic effects against five cancer lines were investigated. Two new ent-abietane diterpenoids, euphonoids H and I (1–2), as well as their two analogues (3–4) were first isolated from this source. The structures of the two new compounds were elucidated on the basis of spectroscopic data and quantum chemical calculation. Their absolute configurations were assigned via ECD spectrum calculation. The isolated compounds were evaluated for their antiproliferative activities against five cancer cell lines. Compounds 1 and 2 exhibited significant inhibitory effects against human prostate cancers C4-2B and C4-2B/ENZR cell lines with IC50 values ranging from 4.16 ± 0.42 to 5.74 ± 0.45 μM. 相似文献
47.
Yan-Ping Liu Qing Wen Shi Hu Yan-Lei Ma Zhi-Hua Jiang Jin-Ying Tang 《Natural product research》2019,33(8):1169-1174
Phytochemical investigation on the stems and leaves of Trigonostemon howii resulted in the isolation of a new abietane diterpenoid, trigohowimine A (1), along with seven known structurally diverse diterpenoids (2–8). The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparison with data reported in the literature. New compound 1 was evaluated for its cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480. Compound 1 showed significant inhibitory effects against various human cancer cell lines with IC50 values ranging from 0.82 to 8.53 μM. 相似文献
48.
建立灵敏表征乌头类双酯型生物碱(DDA)对嗜热四膜虫生长代谢影响的评价方法. 采用微量热法, 在不同给药条件下, 以表达功率-时间曲线(热谱曲线)的特征参数生长速率常数(k)、半数抑制浓度(IC50)、最大输出功率(Pmax)及达峰时间(tp)和总产热量(Qt)为指标, 对嗜热四膜虫生长代谢程度进行客观地量化评价. 结果表明, 随着3种DDA浓度的增加, 达峰时间tp延长, 生长速率常数k、最大输出功率Pmax等随之降低, 且生长速率常数k与相应的浓度间呈现良好的线性关系: r乌头碱=0.9910 (IC50=207.7 μg•mL-1); r新乌头碱=0.9923 (IC50=412.5 μg•mL-1); r次乌头碱=0.9977 (IC50=1497 μg•mL-1). 同时由半抑制浓度IC50得到3种DDA毒性的大小顺序: 乌头碱>新乌头碱>次乌头碱. 初步构效关系研究表明, 在化合物C(3)上引入羟基(OH)以及N原子上引入乙基(CH2CH3)均可明显增加双酯型生物碱对嗜热四膜虫的毒性作用. 相似文献
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50.
Chun-Xue Zhao Bing-Qian Li Zhao-Xiang Shao Da-Hong Li Yong-Kui Jing Zhan-Lin Li Hui-Ming Hua 《Tetrahedron letters》2019,60(43):151154
A new cephalotane diterpenoid glucoside, cephasinenoside A (1), was isolated from the twigs and leaves of Cephalotaxus sinensis (Rehd. et Wils.) Li. The structure of 1 was established on the basis of spectroscopic analyses and ECD calculations. Compound 1 represents the first cephalotane diterpenoid glycoside which inhibits the proliferation of human acute myeloid leukemia HL-60 cells with a GI50 value of 7.17 ± 1.03 μM. 相似文献