共查询到19条相似文献,搜索用时 265 毫秒
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在甾体的甾核或支链上引入不同的官能团后可得到不同生理活性的化合物,它们有可能会成为人类治疗不同疾病的药物,因此甾体药物除了作为传统激素类药物使用外,在抗肿瘤药物、抗炎药物中的应用也成为甾体的重要研究内容之一。含有酰胺官能团的甾体化合物具有很好的生物活性。本文按照酰胺基团在甾体酰胺化合物中的位置进行分类,同时结合本课题组在甾体酰胺化合物的合成和生理活性研究方面所取得的一些成果,概述了近几年来新合成及发现的甾体酰胺类化合物及其衍生物的生理活性及研究进展,包括作为抗肿瘤药物的甾体酰胺化合物的设计、筛选、对5α-还原酶的抑制作用、抑制肿瘤细胞生长增殖活性及抗菌作用,并对此方面的发展趋势、应用前景作了展望。 相似文献
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甾体化合物是一类生物体中广泛存在并起重要功能的生物分子。其特殊结构使这类化合物具有亲脂性,膜亲合性以及与低密度脂蛋白的特异性结合等性能。利用这些特性设计合成各种药物分子的甾体缀合物,可增加药物分子的脂溶性,提高跨膜渗透能力,在特定组织中的分布以及甾体缀合物自身具有独特的生物活性,对探索新型生物活性分子具有重要意义。本文介绍了近年来在设计合成新型甾体缀合物领域的研究进展,包括甾体药物缀合物、含磷甾体缀合物、作为离子通道和分子载体的缀合物及甾体二聚缀合物等。 相似文献
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近年来,分子内环加成反应已广泛用于甾体化合物全合成,其主要一步是由取代的苯并环丁烯热裂而成的5,6-二亚甲基-1,3-环己二烯发生区域专一和立体选择性的环加成反应,构成甾体骨架。现在用此法已合成了一系列消旋和光学活性的甾体化合物。 相似文献
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Vanessa Brito Gilberto Alves Paulo Almeida Samuel Silvestre 《Molecules (Basel, Switzerland)》2021,26(7)
Steroids constitute a unique class of chemical compounds, playing an important role in physiopathological processes, and have high pharmacological interest. Additionally, steroids have been associated with a relatively low toxicity and high bioavailability. Nowadays, multiple steroidal derivatives are clinically available for the treatment of numerous diseases. Moreover, different structural modifications on their skeleton have been explored, aiming to develop compounds with new and improved pharmacological properties. Thus, steroidal arylidene derivatives emerged as a relevant example of these modifications. This family of compounds has been mainly described as 17β-hydroxysteroid dehydrogenase type 1 and aromatase inhibitors, as well as neuroprotective and anticancer agents. Besides, due to their straightforward preparation and intrinsic chemical reactivity, steroidal arylidene derivatives are important synthetic intermediates for the preparation of other compounds, particularly bearing heterocyclic systems. In fact, starting from arylidenesteroids, it was possible to develop bioactive steroidal pyrazolines, pyrazoles, pyrimidines, pyridines, spiro-pyrrolidines, amongst others. Most of these products have also been studied as anti-inflammatory and anticancer agents, as well as 5α-reductase and aromatase inhibitors. This work aims to provide a comprehensive overview of steroidal arylidene derivatives described in the literature, highlighting their bioactivities and importance as synthetic intermediates for other pharmacologically active compounds. 相似文献
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Li HL Tang J Liu RH Lin M Wang B Lv YF Huang HQ Zhang C Zhang WD 《Rapid communications in mass spectrometry : RCM》2007,21(6):869-879
Electrospray ionization multi-stage mass spectrometry (ESI-MS(n)) was performed to study the fragmentation behaviour of seventeen steroidal alkaloids (4 protoverine-type alkaloids, 10 germine-type alkaloids and 3 zygadenin-type alkaloids) from the Chinese herb Veratrum nigrum L. The MS(n) spectra of the [M+H](+) ions for steroidal alkaloids provided a wealth of structural information on the substituted groups. In positive ion mode, the three types of alkaloids showed very different characteristic ions: m/z 436 or 418 for protoverine-type alkaloids; m/z 438, 420 or 402 for germine-type alkaloids; m/z 440 or 422 for zygadenin-type alkaloids. These fragments were used to deduce their mass spectral fragmentation mechanisms. Furthermore, the primary compounds in methanolic extracts of the herb of Veratrum nigrum L. were investigated by using liquid chromatography (LC)/ESI-MS(n). As a result, 21 steroidal alkaloids (5 protoverine-type alkaloids, 14 germine-type alkaloids and 2 zygadenin-type alkaloids) were selectively identified from 27 determined peaks. Eleven compounds were unambiguously identified by comparing with standard compounds and ten compounds were tentatively identified or deduced according to their MS(n) data. Two of these compounds (xingangermine and deacetyl xinganveratrine) were found to be novel steroidal alkaloids. In addition, the chemical structures of two pairs of steroidal alkaloid isomers were deduced by comparing their fragment ions. Given the important structural information of known and unknown steroidal alkaloids in crude herbal extracts, this study is useful for identifying these types of steroidal alkaloids in crude materials rapidly and selectively. 相似文献
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Kapou A Benetis NP Durdagi S Nikolaropoulos S Mavromoustakos T 《Journal of chemical information and modeling》2008,48(11):2254-2264
Thirty-eight antileukemic steroidal esters possessing conformationally flexible nitrogen mustards were studied, and the 3D QSAR/CoMFA and CoMSIA methodologies were applied in order to derive the correlation between their structure and the in vivo antileukemic activity. These compounds show significantly reduced toxicity and possibly increased bioavailability compared to free nitrogen mustards and therefore constitute potent antileukemic drugs. Both the CoMFA and CoMSIA studies gave similar results indicating that the steric effect and the hydrophobic/hydrophilic balance especially in the steroidal part of the molecules probably determined their bioactivity. Of paramount interest is the observation that the orientation of the alkylating part of the SMEs toward the surface of ring B of the steroidal skeleton was related with increased activity. Concerning the steroidal part, the presence of hydrophobic groups in rings B and D was found to be important for enhanced activity. Enhancement of antileukemic potency is further observed if hydrophilic/H-bond acceptor groups are present at the positions 7 and 17 of the steroidal skeleton. Leapfrog simulations provided novel compounds which lead our future synthetic endeavor for obtaining SMEs with optimum bioactivity. 相似文献
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Liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (LC/ESI-QTOF-MS/MS) was performed to study the fragmentation behaviors of steroidal alkaloids from Fritillaria species, the antitussive and expectorant herbs widely used in traditional Chinese medicine. We propose, herein, a strategy that combining key diagnostic fragment ions and the relative abundances and amounts of major fragment ions (the ions exceeding 10% in abundance) to distinguish different sub-classes of Fritillaria alkaloids (FAs). It was found that hydrogen rearrangement and induction effects result in ring cleavage of the basic skeletons occurred in the MS/MS process and produced characteristic fragment ions, which are useful for structural elucidation. This method was finally used to investigate the primary steroidal alkaloids in the extracts of eight major Fritillaria species. As a result, 41 steroidal alkaloids (29 cevanine type, 1 jervine type, 6 veratramine type and 5 secosolanidine type alkaloids) were selectively identified in these Fritillaria species. Twenty-six compounds were unambiguously identified by comparing with the reference compounds and 15 compounds were tentatively identified or deduced according to their MS/MS data. Logical fragmentation pathways for different types of FAs have been proposed and are useful for the identification of these types of steroidal alkaloids in natural products especially when there are no reference compounds available. 相似文献
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Mahboob Alam M. Mushfiq 《中国化学快报》2008,19(2):133-136
The preparation of hitherto unknown steroidal heterocycles containing pyrazole fused to 6,7-position of the steroidal nucleus is described. These heterocycles were prepared by the action of Vilsmeier reagent with steroidal semicarbazones in DMF. The structure of the compounds has been established on the basis of their elemental analysis and spectral data. A general mechanistic scheme for these reactions is also suggested based on current and previous results. 相似文献
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Novel steroidal (6R)‐spiro‐1,3,4‐thiadiazoline derivatives were synthesized by the cyclization of steroidal thiosemicarbazones with acetic anhydride, screened in vitro against antibacterial activity using disc‐diffusion method and the minimum inhibitory concentration. The results showed that steroidal thiadiazoline derivatives exhibited better antibacterial activity than the steroidal thiosemicarbazone derivatives. Chloro and acetoxy substituents on the 3β‐position of the steroidal thiadiazoline ring increased the antibacterial activity. Among all the compounds, compound 7 and 8 were found better inhibitors of both types of bacteria (Gram‐positive and Gram‐negative) as compared to the respective drug amoxicillin. All the synthesized compounds were well characterized by spectroscopic methods such as IR, 1H‐NMR, 13C‐NMR mass, and elemental analysis and their stereochemistry was also discussed. 相似文献
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Matias Kopperi José Ruiz-Jiménez Janne I. Hukkinen Marja-Liisa Riekkola 《Analytica chimica acta》2013
The applicability of comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry to the screening of steroidal compounds in wastewater is demonstrated. Advanced software was utilized to identify unknown compounds in complex two-dimensional chromatograms exploiting retention indices and two different mass spectral databases. Response factors calculated as a function of the individual mass spectra of six commercial standards at different concentrations were used to develop a model allowing the quantitation of all steroidal compounds identified in the sample. The model, based on partial least squares regression equations, provided good accuracy (prediction error < 16%) in the quantitation of steroidal compounds, so offering a valuable alternative to conventional quantitation methods where reference compounds are required for the verification of analytical measurements. Special attention was paid to the development of an exhaustive sample preparation method for the separate analysis of conjugated and free steroids in both water phase and suspended solid particles. The method, including the exploitation of chemometrics, was successfully applied to the determination of steroidal compounds in effluent and influent waters collected at a local wastewater treatment plant. 相似文献
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Novel steroidal (6R)‐spiro‐1,3,4‐thiadiazoline derivatives have been synthesized by the cyclization of steroidal thiosemicarbazones. Thiosemicarbazones have been synthesized by the reaction of steroidal ketones with thiosemicarbazide. All the compounds have been characterized by IR, 1H NMR, mass and elemental analyses. The antibacterial activities of these compounds have been first tested in vitro by the disk diffusion assay against two Gram‐positive and two Gram‐negative bacteria, and then the minimum inhibitory concentration (MIC) values have been determined with the reference of standard drug amoxicillin. The results showed that steroidal thiadiazoline derivatives exhibited better antibacterial activity than the steroidal thiosemicarbazone derivatives. Chloro and acetoxy substituents on the 3β‐position of the steroidal thiadiazoline ring increased the anti‐bacterial activity. Among all the compounds, compounds 7 and 8 were found better inhibitors as compared to the respective drug amoxicillin. 相似文献