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601.
602.
A new binary carbazole alkaloid,8,8″-biskoenigine (1), along with its monomer, koenigine,was isolated from the dried leaves of Murraya koenigii collected in Xishuangbanna, Yunnan province. The structure of 1 was established spectroscopic methods. 相似文献
603.
Masashi TsudaTakao Mugishima Kazusei KomatsuTeruo Sone Michiko TanakaYuzuru Mikami Motoo ShiroManabu Hirai Yasushi OhizumiJun'ichi Kobayashi 《Tetrahedron》2003,59(18):3227-3230
A new pentacyclic oxindole alkaloid, speradine A (1), was isolated from the cultured broth of a fungus Aspergillus tamarii, which was separated from driftwood at a seashore in Okinawa. The structure and relative stereochemistry were determined by spectroscopic data and a single crystal X-ray diffraction analysis. 相似文献
604.
Takashi Harayama Akihiro Hori Georgeta Serban Yoshiaki Morikami Takuya Matsumoto Hitoshi Abe Yasuo Takeuchi 《Tetrahedron》2004,60(47):10645-10649
The total synthesis of luotonin A was achieved in excellent yield by using a Pd-assisted biaryl coupling reaction of N-(bromoquinolinyl)methylquinazolinone with Cy3P and KOAc. The successive treatment of luotonin A with NBS and aq. AgNO3 gave luotonin B in good yield. Although the Pd-assisted coupling reaction of N-(2-bromoindolyl)ethylquinazolinone with Cy3P and KOAc yielded rutaecarpine in poor yield, N-acetate under the same reaction conditions yielded the desired rutaecarpine directly in excellent yield. 相似文献
605.
A.Norrie PearceDavid R. Appleton Russell C. BabcockBrent R. Copp 《Tetrahedron letters》2003,44(20):3897-3899
Distomadines A and B, novel tetracyclic guanidine-containing 6-hydroxyquinoline alkaloids were isolated from the New Zealand ascidian Pseudodistoma aureum and characterised by interpretation of spectroscopic data and chemical derivatisation. Distomadine A exhibited mild antifungal activity but failed to exhibit any biological activity in a range of antitumour, cytotoxicity, anti-inflammatory, and antimycobacterial tests. The known methyl esters of fatty acids eicosapentaenoic acid (EPA), docosahexaenoic acid and eicosatetraenoic acid were also identified in the extract with EPA methyl ester exhibiting mild cytotoxicity to a non-malignant cell line. 相似文献
606.
Introduction AconitumsinomantanumNakai(GaowutouinChi nese)isdistributedinthenorthwesternareaofChina,anditsroots(RAS)areexternallyusedasakindof folkmedicineinChina.Themainactiveconstituentsof RASarenorditerpenoidalkaloids.Themajoralkaloid,lappaconitine,was… 相似文献
607.
我国二萜生物碱化学的研究进展(1986~1992) 总被引:3,自引:0,他引:3
本文综述了我国1986~1992年之间在二萜生物碱化学反应方面的研究。 相似文献
608.
Toshio Honda Hidenori NamikiHiromasa Nagase Hirotake Mizutani 《Tetrahedron letters》2003,44(15):3035-3038
Enantiospecific total synthesis of an indolizidine alkaloid, ipalbidine, was achieved starting from (−)-pyroglutamic acid by employing an intramolecular McMurry coupling reaction with a low-valent titanium, as a key step. 相似文献
609.
Using the Pictet–Spengler reactions of tryptophan with aldehydes under acidic conditions at ambient temperature, diastereoisomers of 1,3-disubstituted-1,2,3,4-tetrahydro-β-carbolines could readily be furnished in short time (0.5–4 h) with good to excellent yields (50–98%). Though intrinsically slow in reaction rates, ketone reactions can be accelerated (from days to minutes) using microwaves in open vessels with high isolated yields (67–99%), making those carbolines feasible reaction intermediates for the synthesis of both natural and unnatural indole alkaloids. Preparation of two indole alkaloids, tetrahydro-β-carbolinediketopiperazines and tetrahydro-β-carbolinehydantoins, were briefly discussed. 相似文献
610.
Sunit Suksamrarn Narisara Suwannapoch Mayuso Kuno Rachada Haritakun Somsak Ruchirawat 《Tetrahedron》2005,61(5):1175-1180
Bioassay-guided fractionation of the EtOAc extract of the roots of Thai Ziziphus oenoplia var. brunoniana resulted in the isolation of four new 13-membered cyclopeptide alkaloids of the 5(13) type, ziziphine N-Q. The structures of the new metabolites were elucidated on the basis of spectroscopic analyses and the stereochemical assignments were established by comparison with other related compounds of known stereochemistry. Ziziphine N and Q exhibited significant antiplasmodial activity against the parasite Plasmodium falciparum with the inhibitory concentration (IC50) values of 3.92 and 3.5 μg/mL, respectively. Ziziphine N and Q also demonstrated weak antimycobacterial activity against Mycobacterium tuberculosis with the same MIC value of 200 μg/mL. 相似文献