前列环素(PGI2)及其类似物的合成

本文综述了前列环素及其类似物的合成。类似物包括有7-羰基—、10,10-二氟—、5-氯—,4-羰基—、6,9-硫—、6,9-氮—,6 a-碳—前列环素以及苯前列环素等。前列环素及其类似物是一类具有抑制血小板聚集的生物活性化合物。     

Chemical Synthesis and In Vitro Antitumor Activity of Quinizarin Glycoside Analogs

A series of new glycoside derivatives of quinizarin were synthesized and characterized by NMR and IR spectrometry, and in vitro antitumor activity of some of these derivatives was evaluated against the mouse leukaemia P388 and the human leukaemia HL-60 cell lines by the standard MTT assay. They were proven to possess moderate antitumor activity.     

Thiazole Analogs of Isoflavolignans

Modified analogs of isoflavolignans are prepared by annelation of dioxole, dioxane, and dioxepan fragments to 3-thiazolyl-7,8-dihydroxychromones     

N-Alkylamides from Piper longum L. and their stimulative effects on the melanin content and tyrosinase activity in B16 melanoma cells

Abstract

Piper longum L., known as long pepper, is an edible and medicinal plant used as spice and for the treatment of stomach disease and analgesia in traditional Chinese medicine. N-Alkylamides are the major secondary metabolites in this plant. Sixteen known N-alkylamides were isolated from P. longum. Their structures were established on the basis of spectroscopic data and comparison to reported literatures. Among them, five compounds were isolated from this plant for the first time. Ethanol extract, compounds 1, 2, 3, 7 and 11 exhibited potent ability to increase the melanin content and weak stimulative effect on the tyrosinase activity in a concentration-dependent manner. Moreover, compound 2 also presented strong capacity to increase the tyrosinase activity in a concentration-dependent manner. These results indicated that P. longum might be a good natural source of lead compound for skin disorder diseases.     

Synthesis and Biological Activity of Philanthotoxin Analogs

Sodium ion channels, acetylcholine esterase and neurotransmitter receptors in insect neurons and skeletal muscles are often made as target by practical neurotoxic pesticides. But insects can create resistance after using a pesticide for a long time. So th…     

伞型酮类似物的合成及抗菌作用

2-甲基间二酚或5-甲基间二酚分别与dl-苹果酸或乙酰乙酸乙酯, 在浓硫酸催化下, 经Peachmann缩合反应得到伞型酮(7-羟基香豆素)类似物5～7. 5～7经甲基化得新化合物5a, 6a和7a; 经Williamson反应, TBAB(四正丁基溴化铵)相转移催化合成了14个新的香豆素类化合物5b～5e, 6b～6f, 7b～7f. 经IR, MS, ¹H NMR及元素分析对所有化合物的结构进行了表征. 初步生物活性实验结果表明, 在50 μg/mL浓度下, 化合物6对辣椒疫霉病菌(Phytophythora capsici)抑制率达58.5%, 化合物7c对番茄灰霉病菌(Botrytis cinerea)抑制率为54.0%, 化合物6c对水稻纹枯病菌(Rhizoctonia solani)的抑制率达83.7%.     

Facile Synthesis of Isodamascone and Its Analogs

Synthesis of isodamascone and its analogs, the commercially important aroma compounds, have been accomplished from the readily available 1,5,5‐trimethyl‐2‐cyclohexen‐1‐ol via a short, facile, and simple sequence of reactions in excellent yield.     

L-苯丙氨酸衍生物的一锅法合成及其抗/促凝活性

氨基酸及其衍生物在止血/抗凝活性方面有一定的应用。以L-苯丙氨酸为起始原料,经磺化引入磺酸基,再与甲醇、乙醇、丙醇、异丙醇和正丁醇脱水酯化,一锅法合成了6种未见报道的L-苯丙氨酸的磺酸酯类衍生物(L1~L6),以期获得具有的较强血液生理活性的潜在药物。实验中采用了质谱、核磁共振进行结构表征。该合成方法产率高(78%~95%),后处理简单,不失为合成该类衍生物的好方法。衍生物的凝血四项实验表明:抗促凝效果是内源性和外源性凝血途径共同作用的结果。血浆复钙实验表明:衍生物均具有一定的抗凝活性,其抗凝效果随浓度变化而变化,但是随R链的长度增加,抗凝效果并未见规律性。衍生物的抗凝活性主要受磺酸基及酯基的影响,因此在设计合成抗血栓化合物时可以考虑引入磺酸基及酯类基团。     

Enhancement of the Antioxidant and Skin Permeation Properties of Betulin and Its Derivatives

This study investigated the antioxidant activity DPPH, ABTS, and Folin–Ciocalteu methods of betulin (compound 1) and its derivatives (compounds 2–11). Skin permeability and accumulation associated with compounds 1 and 8 were also examined. Identification of the obtained products (compound 2–11) and betulin isolated from plant material was based on the analysis of ¹H- NMR and ¹³C-NMR spectra. The partition coefficient was calculated to determine the lipophilicity of all compounds. In the next stage, the penetration through pig skin and its accumulation in the skin were evaluated of ethanol vehicles containing compound 8 (at a concentration of 0.226 mmol/dm³), which was characterized by the highest antioxidant activity. For comparison, penetration studies of betulin itself were also carried out. Poor solubility and the bioavailability of pure compounds are major constraints in combination therapy. However, we observed that the ethanol vehicle was an enhancer of skin permeation for both the initial betulin and compound 8. The betulin 8 derivative showed increased permeability through biological membranes compared to the parent betulin. The paper presents the transformation of polycyclic compounds to produce novel derivatives with marked antioxidant activities and as valuable intermediates for the pharmaceutical industry. Moreover, the compounds contained in the vehicles, due to their mechanism of action, can have a beneficial effect on the balance between oxidants and antioxidants in the body, minimizing the effects of oxidative stress. The results of this work may contribute to knowledge regarding vehicles with antioxidant potential. The use of vehicles for this type of research is therefore justified.     

Thermodynamic Properties of Anabasine Hydrochloride and Its Analogs

The heats of solution of anabasine hydrochloride C10H14N2HCl and of the reaction of its aqueous solution with crystalline AgNO₃ at various dilutions were determined. The standard enthalpies of formation of anabasine hydrochloride and its 36 analogs were calculated. The temperature dependence of the anabasine hydrochloride heat capacity was studied within the 173-448 K range.     

Conformational Properties of Ethane and Its Analogs in Nanotubes

Russian Journal of General Chemistry - Modern approaches to understanding the origin of the internal rotation barrier in ethane and its analogs were reviewed. Computer simulation revealed the...     

Sulforaphane and Its Bifunctional Analogs: Synthesis and Biological Activity

For decades, various plants have been studied as sources of biologically active compounds. Compounds with anticancer and antimicrobial properties are the most frequently desired. Cruciferous plants, including Brussels sprouts, broccoli, and wasabi, have a special role in the research studies. Studies have shown that consumption of these plants reduce the risk of lung, breast, and prostate cancers. The high chemopreventive and anticancer potential of cruciferous plants results from the presence of a large amount of glucosinolates, which, under the influence of myrosinase, undergo an enzymatic transformation to biologically active isothiocyanates (ITCs). Natural isothiocyanates, such as benzyl isothiocyanate, phenethyl isothiocyanate, or the best-tested sulforaphane, possess anticancer activity at all stages of the carcinogenesis process, show antibacterial activity, and are used in organic synthesis. Methods of synthesis of sulforaphane, as well as its natural or synthetic bifunctional analogues with sulfinyl, sulfanyl, sulfonyl, phosphonate, phosphinate, phosphine oxide, carbonyl, ester, carboxamide, ether, or additional isothiocyanate functional groups, and with the unbranched alkyl chain containing 2–6 carbon atoms, are discussed in this review. The biological activity of these compounds are also reported. In the first section, glucosinolates, isothiocyanates, and mercapturic acids (their metabolites) are briefly characterized. Additionally, the most studied anticancer and antibacterial mechanisms of ITC actions are discussed.     

Molecular Determinant of DIDS Analogs Targeting RAD51 Activity

RAD51 is the central protein in DNA repair by homologous recombination (HR), involved in several steps of this process. It is shown that overexpression of the RAD51 protein is correlated with increased survival of cancer cells to cancer treatments. For the past decade, RAD51 overexpression-mediated resistance has justified the development of targeted inhibitors. One of the first molecules described to inhibit RAD51 was the 4,4′-diisothiocyanato-stilbene-2,2′-disulfonic acid (DIDS) molecule. This small molecule is effective in inhibiting different functions of RAD51, however its mode of action and the chemical functions involved in this inhibition have not been identified. In this work, we used several commercial molecules derived from DIDS to characterize the structural determinants involved in modulating the activity of RAD51. By combining biochemical and biophysical approaches, we have shown that DIDS and two analogs were able to inhibit the binding of RAD51 to ssDNA and prevent the formation of D-loop by RAD51. Both isothiocyanate substituents of DIDS appear to be essential in the inhibition of RAD51. These results open the way to the synthesis of new molecules derived from DIDS that should be greater modulators of RAD51 and more efficient for HR inhibition.     

Development of a Kilogram-Scale Synthesis of Salidroside and Its Analogs

An efficient, safe, and viable process has been developed for large-scale preparation of salidroside, a natural product. The process consists of two chemical steps, which produce the salidroside on a multikilogram scale with 72% overall yield and >98% purity. A series of novel salidroside analogs were prepared according to the same method.

含嘧啶环乙二酰胺类化合物的合成及其对小菜蛾酪氨酸酶的抑制作用

酪氨酸酶在昆虫体内起着很重要的生理作用,控制酪氨酸酶的活性即可调节昆虫的生长行为,借鉴曲酸和铜铁试剂的杂原子螯合机理,设计了一类含嘧啶环乙二酰胺的新型化合物,以取代苯胺为起始原料经3步反应合成了目标化合物,其结构通过红外、核磁氢谱、质谱、高分辨质谱表征.生物活性测试表明该系列化合物对小菜蛾酪氨酸酶活性有一定的抑制作用.     

Synthesis,biological evaluation and SAR studies of benzimidazole derivatives as H1-antihistamine agents

A series of benzimidazole derivatives have been designed,synthesized and evaluated for H₁ antihistamine activity.Six compounds have showed potent antihistamine H₁ activity.The primary SAR analysis indicated that benzyl or benzylidinyl substituted on the exo-nitrogen atom and C2 of the benzimidazole were significant.Further experiments indicated that compound 17d displayed excellent activity to reduce mast cell degranulation,moderate anti-PAF activity and decreased potency on hERG compared to astermizole.Hence compound 17d could serve as anti-allergic agent for further development.     

Synthesis of Sugar and Nucleoside Analogs and Evaluation of Their Anticancer and Analgesic Potentials

Chemical modification of sugars and nucleosides has a long history of producing compounds with improved selectivity and efficacy. In this study, several modified sugars (2–3) and ribonucleoside analogs (4–8) have been synthesized from α-d-glucose in a total of 21 steps. The compounds were tested for peripheral anti-nociceptive characteristics in the acetic acid-induced writhing assay in mice, where compounds 2, 7, and 8 showed a significant reduction in the number of writhes by 56%, 62%, and 63%, respectively. The compounds were also tested for their cytotoxic potential against human HeLa cell line via trypan blue dye exclusion test followed by cell counting kit-8 (CCK-8) assay. Compound 6 demonstrated significant cytotoxic activity with an IC₅₀ value of 54 µg/mL. Molecular docking simulations revealed that compounds 2, 7, and 8 had a comparable binding affinity to cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) enzymes. Additionally, the bridged nucleoside analogs 7 and 8 potently inhibited adenosine kinase enzyme as well, which indicates an alternate mechanistic pathway behind their anti-nociceptive action. Cytotoxic compound 6 demonstrated strong docking with cancer drug targets human cytidine deaminase, proto-oncogene tyrosine-protein kinase Src, human thymidine kinase 1, human thymidylate synthase, and human adenosine deaminase 2. This is the first ever reporting of the synthesis and analgesic property of compound 8 and the cytotoxic potential of compound 6.     

Tyrosinase Inhibitors Naturally Present in Plants and Synthetic Modifications of These Natural Products as Anti-Melanogenic Agents: A Review

Tyrosinase is a key enzyme target to design new chemical ligands against melanogenesis. In the current review, different chemical derivatives are explored which have been used as anti-melanogenic compounds. These are different chemical compounds naturally present in plants and semi-synthetic and synthetic compounds inspired by these natural products, such as kojic acid produced by several species of fungi; arbutin—a glycosylated hydroquinone extracted from the bearberry plant; vanillin—a phenolic aldehyde extracted from the vanilla bean, etc. After enzyme inhibition screening, various chemical compounds showed different therapeutic effects as tyrosinase inhibitors with different values of the inhibition constant and IC₅₀. We show how appropriately designed scaffolds inspired by the structures of natural compounds are used to develop novel synthetic inhibitors. We review the results of numerous studies, which could lead to the development of effective anti-tyrosinase agents with increased efficiency and safety in the near future, with many applications in the food, pharmaceutical and cosmetics industries.     

他克林二联体类似物的合成和药理研究进展

他克林二联体及其类似物是一类药效明显的乙酰胆碱酯酶抑制剂，按AnA,AnX,XnX和AnH(A)等四种类型系统地综述了其合成和药理研究进展。参考文献28篇。