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排序方式: 共有91条查询结果,搜索用时 15 毫秒
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2.
Poojali P. Warekar Priyanka T. Patil Kirti T. Patil Dattatraya K. Jamale Govind B. Kolekar 《合成通讯》2016,46(24):2022-2030
An ecofriendly route has been investigated for the synthesis of 4-(4-nitro-phenyl)-2-phenyl-1,4-dihydro-benzo[4,5]imidazo[1,2-a]pyrimidine-3-carboxylic acid ethyl ester derivatives by one-pot, three-component condensation of ethyl benzoylacetate, aromatic aldehydes, and 2-amino benzimidazole using 260?mol% of citric acid as reaction mediator. Citric acid is an inexpensive, nontoxic, and green medium with smoothly activates the rate of reaction. The synthesized compounds were assessed for in vitro antimycobacterial activity against Mycobacterium tuberculosis H37RV strain using the microplate alamar blue assay (MABA). The results indicate that among all the synthesized compound series, P-4 and P-9 compounds illustrate effective activity with a minimum inhibitory concentration of 25?µg/ml. 相似文献
3.
Kok Tong Wong Hasnah Osman Thaigarajan Parumasivam Unang Supratman Mohammad Tasyriq Che Omar Mohamad Nurul Azmi 《Molecules (Basel, Switzerland)》2021,26(7)
A total of fourteen pyrazoline derivatives were synthesized through cyclo-condensation reactions by chalcone derivatives with different types of semicarbazide. These compounds were characterized by IR, 1D-NMR (1H, 13C and Distortionless Enhancement by Polarization Transfer - DEPT-135) and 2D-NMR (COSY, HSQC and HMBC) as well as mass spectroscopy analysis (HRMS). The synthesized compounds were tested for their antituberculosis activity against Mycobacterium tuberculosis H37Ra in vitro. Based on this activity, compound 4a showed the most potent inhibitory activity, with a minimum inhibitory concentration (MIC) value of 17 μM. In addition, six other synthesized compounds, 5a and 5c–5g, exhibited moderate activity, with MIC ranges between 60 μM to 140 μM. Compound 4a showed good bactericidal activity with a minimum bactericidal concentration (MBC) value of 34 μM against Mycobacterium tuberculosis H37Ra. Molecular docking studies for compound 4a on alpha-sterol demethylase was done to understand and explore ligand–receptor interactions, and to hypothesize potential refinements for the compound. 相似文献
4.
Ntombizethu Nokuphiwa Msomi Tiara Padayachee Nomfundo Nzuza Puleng Rosinah Syed Justyna Dorota Kry Wanping Chen Dominik Gront David R. Nelson Khajamohiddin Syed 《Molecules (Basel, Switzerland)》2021,26(6)
The impact of lifestyle on shaping the genome content of an organism is a well-known phenomenon and cytochrome P450 enzymes (CYPs/P450s), heme-thiolate proteins that are ubiquitously present in organisms, are no exception. Recent studies focusing on a few bacterial species such as Streptomyces, Mycobacterium, Cyanobacteria and Firmicutes revealed that the impact of lifestyle affected the P450 repertoire in these species. However, this phenomenon needs to be understood in other bacterial species. We therefore performed genome data mining, annotation, phylogenetic analysis of P450s and their role in secondary metabolism in the bacterial class Gammaproteobacteria. Genome-wide data mining for P450s in 1261 Gammaproteobacterial species belonging to 161 genera revealed that only 169 species belonging to 41 genera have P450s. A total of 277 P450s found in 169 species grouped into 84 P450 families and 105 P450 subfamilies, where 38 new P450 families were found. Only 18% of P450s were found to be involved in secondary metabolism in Gammaproteobacterial species, as observed in Firmicutes as well. The pathogenic or commensal lifestyle of Gammaproteobacterial species influences them to such an extent that they have the lowest number of P450s compared to other bacterial species, indicating the impact of lifestyle on shaping the P450 repertoire. This study is the first report on comprehensive analysis of P450s in Gammaproteobacteria. 相似文献
5.
Rhea C. Garcellano John R. Cort Syed G. A. Moinuddin Scott G. Franzblau Rui Ma 《Natural product research》2020,34(8):1175-1179
AbstractCoronaridine (1) was isolated from the CH2Cl2 root extract of Tabernaemontana ternifolia. The structure of 1 was established from 1D- and 2D-NMR and HR-ESIMS experiments, and by comparison with reported spectroscopic data. To date, this is the first report of compound 1 from T. ternifolia, introduced as new Tabernaemontana species from Philippines in 2005 on the basis of morphological characters. Coronaridine, an iboga-type indole alkaloid, has been isolated from over 50 Tabernaemontana species and can thus be inferred as a chemotaxonomic marker of the genus. T. ternifolia has a distinct arrangement of leaves not known in the genus, but is variable in other genera. Its isolation from endemic T. ternifolia establishes its position in the genus and supports the claim that coronaridine is a chemical marker of the genus Tabernaemontana. Interestingly, coronaridine exhibited relatively weak activity against Mycobacterium tuberculosis H37Rv (MIC 82.64?μg/mL) (Rifampicin MIC 0.05?μg/mL). 相似文献
6.
Liwen Han 《Journal of carbohydrate chemistry》2013,32(5-6):335-382
AbstractLipoarabinomannan (LAM), mannosyl LAM (ManLAM), and mycolyl-arabinogalactan (mAG) are unique and ubiquitous cell wall constituents of Mycobacterium tuberculosis (M. tb), the bacterium causing tuberculosis (TB). It has been well documented that LAM, ManLAM, and mAG play an important role in mycobacterial infections and in the elicitation of specific immune responses against M. tb in the host. Therefore, LAM, ManLAM, mAG, and related molecules are attractive targets for the development of novel TB diagnostic and therapeutic strategies. Accordingly, numerous research groups have spent great effort on the chemical synthesis and biological studies of mycobacterium-related arabinofuranosyl oligosaccharides and their mimetics and conjugates. This article provides an extensive review about the progresses in this area. Due to the page limit of this journal, the review is published in three parts separately. This part (Part II) is focused on the synthesis of various ManLAM and mAG analogs containing mannose, galactose or galactosamine units and other natural structural motifs, as well as arabinofuranosyl oligosaccharide C-analogs and other derivatives. 相似文献
7.
W. Bamogo L. Mugherli A. Banyasz A. Novelli-Rousseau F. Mallard T.-H. Tran-Thi 《Analytica chimica acta》2015
A detection method for nicotinic acid, a specific metabolite marker of Mycobacterium tuberculosis present in cultures and patients' breath, is studied in complex solutions containing other metabolites and in biological media such as urine, saliva and breath condensate. The method is based on the analysis of the luminescence increase of Tb3+ complexes in the presence of nicotinic acid due to the energy transfer from the excited ligand to the lanthanide ion. It is shown that other potential markers found in M. tuberculosis culture supernatant, such as methyl phenylacetate, p-methyl anisate, methyl nicotinate and 2-methoxy biphenyl, can interfere with nicotinic acid via a competitive absorption of the excitation photons. A new strategy to circumvent these interferences is proposed with an upstream trapping of volatile markers preceding the detection of nicotinic acid in the liquid phase via the luminescence of Tb3+ complexes. The cost of the method is evaluated and compared with the Xpert MTB/RIF test endorsed by the World Health Organization. 相似文献
8.
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(10):797-802
The search for new tuberculostatics is important considering the occurrence of drug‐resistant strains of Mycobacterium tuberculosis . Three polymorphs of N ′‐(1,3‐dithiolan‐2‐ylidene)‐4‐nitrobenzohydrazide (a potentially tuberculostatic agent), C10H9N3O3S2, denoted (I1), (I2) and (I3), and the monohydrate of this compound, C10H9N3O3S2·H2O, (I4), have been characterized by single‐crystal X‐ray diffraction. The conformations of the molecules in all these structures are very similar. Structures (I1), (I2) and (I3) provide an example of packing polymorphism resulting from different intermolecular interactions. 相似文献
9.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(3):400-405
The search for new tuberculostatics is an important issue due to the increasing resistance of Mycobacterium tuberculosis to existing agents and the resulting spread of the pathogen. Heteroaryldithiocarbazic acid derivatives have shown potential tuberculostatic activity and investigations of the structural aspects of these compounds are thus of interest. Three new examples have been synthesized. The structure of methyl 2‐[amino(pyridin‐3‐yl)methylidene]hydrazinecarbodithioate, C8H10N4S2, at 293 K has monoclinic (P21/n) symmetry. It is of interest with respect to antibacterial properties. The structure displays N—H…N and N—H…S hydrogen bonding. The structure of N′‐(pyrrolidine‐1‐carbonothioyl)picolinohydrazonamide, C11H15N5S, at 100 K has monoclinic (P21/n) symmetry and is also of interest with respect to antibacterial properties. The structure displays N—H…S hydrogen bonding. The structure of (Z)‐methyl 2‐[amino(pyridin‐2‐yl)methylidene]‐1‐methylhydrazinecarbodithioate, C9H13N4S2, has triclinic (P) symmetry. The structure displays N—H…S hydrogen bonding. 相似文献
10.
P. Singh T. Saha P. Mishra M. K. Parai S. Ireddy S. Lavanya Kumar M. 《SAR and QSAR in environmental research》2016,27(11):883-909
AbstractWe earlier reported thiophene-containing trisubstituted methanes (TRSMs) as novel cores carrying anti-tubercular activity, and identified S006-830 as the phenotypic lead with potent bactericidal activity against single- and multi-drug resistant clinical isolates of Mycobacterium tuberculosis (M. tb). In this work, we carried out additional synthesis of several TRSMs. The reaction scheme essentially followed the Grignard reaction and Friedel–Crafts alkylation, followed by insertion of a dialkylaminoethyl chain. We also performed microbiological evaluations including in vitro screening against the virulent strain M. tb H37Rv, cytotoxicity assessment in the Vero C-1008 cell line, and 3D-QSAR studies with comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA). CoMFA and CoMSIA models yielded good statistical results in terms of q2 and r2 values, suggesting the validity of the models. It was concluded that a para-substituted benzene ring with bulkier electron-donating groups and aminoalkyl chains are required for higher inhibitory capacity against M. tuberculosis. We believe that these insights will rationally guide the design of newer, optimal, TRSMs. 相似文献