共查询到20条相似文献,搜索用时 15 毫秒
1.
Phytochemical investigation of the rhizomes of Smilax trinervula led to isolation and structure elucidation of eight lignan glycosides, including five new lignans, namely, (7S, 8R, 8′R)-4, 4′, 9-trihydroxy-3, 3′, 5, 5′-tetramethoxy-7, 9′-epoxylignan-7′-one 4′-O-β-d-glucopyranoside (1), (7S, 8R, 8′R)-4, 4′, 9-trihydroxy-3, 3′, 5, 5′-tetramethoxy-7, 9′-epoxylignan-7′-one 4-O-β-d- glucopyranoside (2) (7S, 8R)-4, 9, 9′-trihydroxy-3, 3′, 5-trimethoxy-4′, 7-epoxy-8, 5′-neolignan 9′-O-β-d-glucopyranoside (3), (7R, 8R)-4, 9, 9′-trihydroxy-3, 5-dimethoxy-7.O.4′, 8.O.3′- neolignan 9′-O-β-d-glucopyranoside (4), and (7S, 8R)-4, 9, 9′-trihydroxy-3, 3′, 5-trimethoxy-8, 4′-oxy-neolignan 4-O-β-d-glucopyranoside (5), along with three known compounds (6-8). Their structures were established mainly on the basis of 1D and 2D NMR spectral data, ESI–MS and comparison with the literature. Compounds 1-8 were tested in vitro for their cytotoxic activity against four human tumor cell lines (SH-SY5Y, SGC-7901, HCT-116, Lovo). Compounds 3 and 5 exhibited cytotoxic activity against Lovo cells, with IC50 value of 10.4 μM and 8.5 μM, respectively. 相似文献
2.
Xiang-long Wu Min Tian Huai-zhen He Wei Sun Jian-li Li Zhen Shi 《Bioorganic & medicinal chemistry letters》2009,19(11):2957-2959
Two novel chlorinated fluoresceins 2′,4′,5′,7′-tetrachloro-6-(5-carboxypentyl)-4,7-dichloro fluorescein succinimidyl ester (1G) and 2′,4′,5′,7′-tetrachloro-6-(3-carboxypropyl)-4,7-dichlorofluorescein succinimidyl ester (2G) were synthesized as fluorescent probes for labeling proteins. Structures of target compounds and intermediates were determined via IR, MS, 1H NMR and element analysis. The investigation in immunofluorescence histochemistry showed them had strong fluorescence, high photostability and good biocompatibility. 相似文献
3.
Yan-Ping Li Liao-Bin Dong Duo-Zhi Chen Hong-Mei Li Jin-Dong Zhong Fei Li Xing Liu Bei Wang Rong-Tao Li 《Phytochemistry letters》2013,6(2):281-285
(7S,8R,7′S)-9,7′,9′-Trihydroxy-3,4-methylenedioxy-3′-methoxy [7-O-4′,8-5′] neolignan (1) and (7S,8R,7′S)-9,9′-dihydroxy-3,4-methylenedioxy-3′,7′-dimethoxy [7-O-4′,8-5′] neolignan (2), two new natural dihydrobenzofuran-type neolignans, along with 9,9′-dihydroxy-3,4-methylenedioxy-3′-methoxy [7-O-4′,8-5′] neolignan (3) and (-)-machicendiol (4), were isolated from the whole plants of Breynia fruticosa. The structures of 1 and 2, including the absolute configurations, were determined by spectroscopic methods and circular dichroism (CD) techniques. The absolute configuration of 4 was confirmed by calculations of the OR spectrum, together with OR and ECD spectra of its p-bromobenzoate ester (4a). 相似文献
4.
María B. Sabaini María A. Zinni Martina Mohorčič Jožefa Friedrich Adolfo M. Iribarren Luis E. Iglesias 《Journal of Molecular Catalysis .B, Enzymatic》2010,62(3-4):225-229
Candida antarctica lipase B (CAL-B)-catalysed regioselective deacetylation of 2′,3′,5′-tri-O-acetyl-1-β-d-arabinofuranosyluracil (1) and 2′,3′,5′-tri-O-acetyl-9-β-d-arabinofuranosyladenine (2) was studied. The choice of the reaction medium allowed the regioselective formation of products bearing different degree of acetylation: in isopropanol, CAL-B catalysed the formation of the corresponding 2′-O-acetylated arabinonucleosides, while hydrolyses afforded the 2′,3′-di-O-acetylated products. In particular, the procedure herein described allows a simple and efficient preparation of the reported vidarabine prodrug 2′,3′-di-O-acetyl-9-β-d-arabinofuranosyladenine, avoiding the utilisation of protective groups. Moreover, to achieve full deacetylation of the assayed substrates, a set of commercial hydrolases and fungal keratinases from Doratomyces microsporus (DMK) and Paecilomyces marquandii (PMK) were tested. While only PMK and DMK catalysed the quantitative complete deacetylation of 1, DMK accomplished full deacetylation of 2 in shorter time than the other assayed enzymes. 相似文献
5.
Ki-Bong Oh Ji Hye Lee Jong Wook Lee Kyung-Mi Yoon Soon-Chun Chung Heung Bae Jeon Jongheon Shin Hyi-Seung Lee 《Bioorganic & medicinal chemistry letters》2009,19(3):945-948
A series of halophenols was prepared by the reaction of bis(hydroxyphenyl)methanes with effective halogenating agents such as bromine and sulfuryl chloride. One of these compounds, a biologically active halophenol—2,2′,3,3′-tetrabromo-4,4′,5,5′-tetrahydroxydiphenylmethane (1)—frequently isolated from red algae, was synthesized for the first time. Other halophenols included several novel compounds, together with known derivatives that were synthesized from the phenolic intermediates, bis(3,4-dihydroxyphenyl)methane (5) and bis(2-hydroxyphenyl)methane (14). All of the synthesized compounds were tested for antimicrobial activity against Gram-positive, Gram-negative bacteria and fungi. The preliminary structure–activity relationship was investigated in order to determine the essential structural requirements for their antimicrobial activity. Of all these halophenols, 2,2′,3,3′,6-pentabromo-4,4′,5,5′-tetrahydroxydiphenylmethane (8) was found to be the most active against Candida albicans, Aspergillus fumigatus, Trichophyton rubrum, and Trichophyton mentagrophytes while 3,3′,5,5′-tetrachloro-2,2′-dihydroxydiphenylmethane (18) exerted a powerful antibacterial effect against Staphylococcus aureus, Bacillus subtilis, Micrococcus luteus, Proteus vulgaris, and Salmonella typhimurium. 相似文献
6.
Addition of 5-bromo-2′,3′-O-isopropylidene-5′-O-trityluridine (2) in pyridine to an excess of 2-lithio-1,3-dithiane (3) in oxolane at 78° gave (6R)-5,6-dihydro-(1,3-dithian-2-yl)-2′,3′-O-isopropylidene -5′-O-trityluridine (4), (5S,6S)-5-bromo-5,6-dihydro-(1,3-dithian-2-yl)-2′,3′-O-isopropylidene-5′-O-trityluridine (5), and its (5R) isomer 6 in yields of 37, 35, and 10%, respectively. The structure of 4 was proved by Raney nickel desulphurization to (6S)-5,6-dihydro-2′,3′-O-isopropylidene-6-methyl-5′-O-trityluridine (7) and by acid hydrolysis to give D-ribose and (6R)-5,6-dihydro-6-(1,3-dithian-2-yl)uracil (9). Treatment of 4 with methyl iodide in aqueous acetone gave a 30&%; yield of (R,S)-5,6-dihydro-6-formyl-2′,3′-O-isopropylidene-5′-O-trityl-uridine (10), characterized as its semicarbazone 11. Both 5 and 6 gave 4 upon brief treatment with Raney nickel. Both 5 and 6 also gave 6-formyl-2′,3′-O-isopropylidene-5′- O-trityluridine (12) in ~41%; yield when treated with methyl iodide in aqueous acetone containin- 10%; dimethyl sulfoxide. A by-product, identified as the N-methyl derivative (13) of 12 was also formed in yields which varied with the amount of dimethyl sulfoxide used. Reduction of 12 with sodium borohydride, followed by deprotection, afforded 6-(hydroxymethyl)uridine (17), characterized by hydrolysis to the known 6-(hydroxymethyl)uracil (18). Knoevenagel condensation of a mixture of the aldehydes 12 and 13 with ethyl cyanoacetate yielded 38%; of E- (or Z-)6-[(2-cyano-2-ethoxycarbonyl)ethylidene]-2′,3′-O-isopropylidene-5′-O-trityluridine (19) and 10%; of its N-methyl derivative 20. Hydrogenation of 19 over platinum oxide in acetic anhydride followed by deprotection gave R (or S)-6-(3-amino-2-carboxypropyl)uridine (23). 相似文献
7.
A new meroterpenoid, austalide H acid ethyl ester (1), 5-(2′,4′-dihydroxy-6′-methylphenyl)-3-methylfuran-2-carboxylic acid (2), 5-(2′-hydroxy-6′-methylphenyl)-3-methylfuran-2-carboxylic acid (3) and 5-((6′-methyl-4′-oxo-3′,4′-dihydro-2H-pyran-2′-yl)methyl)-3-methylfuran-2-carboxylic acid (4), along with six known compounds, austalides H, J, K, and P (5–8), questin (9) and sulochrin (10) were isolated from the lipophilic extract of the alga-derived fungi Penicillium thomii KMM 4645 and Penicillium lividum KMM 4663. The structures of the isolated compounds were determined based on spectroscopic methods. The austalides showed significant inhibitory activity against endo-1,3-β-d-Glucanase from a crystalline stalk of the marine mollusk Pseudocardium sachalinensis. 相似文献
8.
Selective de-esterification of 1′,2:4,6-di-O-isopropylidenesucrose tetra-acetate2 (1) with methanolic ammonia at ?10° gave an inseparable mixture (2+3) of the 3,4′,6′- and 3,3′,6′-triacetates and also the 4,6′-diacetate 4. When the reaction was performed at 5°, it gave 4, the 4-acetate 8, and the parent diacetal 9. These derivatives allow selective reaction at hydroxyl groups in sucrose, in particular at HO-3′ and, HO-4′, not hitherto possible. Mesylation of 4 gave the 3′,4′-dimesylate 7, which, on treatment with aqueous acetic acid followed by acetylation, afforded 3′,4′-di-O-mesylsucrose hexa-acetate (11). Treatment of 11 with sodium methoxide in methanol at 70° for 1 min gave the ribo-3′,4′-epoxide 12 as the minor, and the lyxo-3′,4′-epoxide 13 as the major, product. Selective tosylation of 4 gave the 3',4'-ditosylate 14 (3.7%), 4′-tosylate 15 (3.1%), and 3'-tosylate 16 (31%), indicating the order of reactivity HO-3′>HO-4′ in 4. De acetalation of 15 and 16 followed by acetylation gave the hepta-acetates of 4′- and 3′-O-tosylsucrose, respectively, which were converted into the respective epoxides, 13 and 12, by methanolic sodium methoxide. 相似文献
9.
Takeshi Kodama Takuya Ito Dya Fita Dibwe So-Yeun Woo Hiroyuki Morita 《Bioorganic & medicinal chemistry letters》2017,27(11):2397-2400
Muchimangins are benzophenone-xanthone hybrid polyketides produced by Securidaca longepedunculata. However, their biological activities have not been fully investigated, since they are minor constituents in this plant. To evaluate the possibility of muchimangins as antibacterial agent candidates, five muchimangin analogs were synthesized from 2,4,5-trimethoxydiphenyl methanol and the corresponding xanthones, by utilizing p-toluenesulfonic acid monohydrate for the Brønsted acid-catalysis. The antibacterial assays against Gram-positive bacteria, Staphylococcus aureus and Bacillus subtilis, and Gram-negative bacteria, Klebsiella pneumoniae and Escherichia coli, revealed that the muchimangin analogs (±)-1,3,6,8-tetrahydroxy-4-(phenyl-(2′,4′,5′-trimethoxyphenyl)methyl)-xanthone (1), (±)-1,3,6-trihydroxy-4-(phenyl-(2′,4′,5′-trimethoxyphenyl)methyl)-xanthone (2), and (±)-1,3-dihydroxy-4-(phenyl-(2′,4′,5′-trimethoxyphenyl)methyl)-xanthone (3) showed significant activities against S. aureus, with MIC values of 10.0, 10.0, and 25.0 μM, respectively. Analogs (±)-1 and (±)-2 also exhibited antibacterial activities against B. subtilis, with MIC values of 50.0 and 12.5 μM, respectively. Furthermore, (+)-3 enhanced the antibacterial activity against S. aureus, with a MIC value of 10 μM. 相似文献
10.
Three new neolignan glucosides (1–3), together with four known analogs (4–7), have been isolated from the stems of Dendrobium aurantiacum var. denneanum. Structures of the new compounds including the absolute configurations were determined by spectroscopic and chemical methods as (−)-(8R,7′E)-4-hydroxy-3,3′,5,5′-tetramethoxy-8,4′-oxyneolign-7′-ene-9,9′-diol 4,9-bis-O-β-d-glucopyranoside (1), (−)-(8S,7′E)-4-hydroxy-3,3′,5,5′-tetramethoxy-8,4′-oxyneolign-7′-ene-9,9′-diol 4,9-bis-O-β-d-glucopyranoside (2), and (−)-(8R,7′E)-4-hydroxy-3,3′,5,5′,9′-pentamethoxy-8,4′-oxyneolign-7′-ene-9-ol 4,9-bis-O-β-d-glucopyranoside (3), respectively. 相似文献
11.
Malcolm MacCoss Fouad S. Ezra MorrisJ. Robins Steven S. Danyluk 《Carbohydrate research》1978,62(2):203-212
A detailed 1H 220-MHz n.m.r. study of 9-(β-d-xylofuranosyl)adenine 3′,5′-cyclic monophosphate (3′,5′-xylo-cAMP, 1) and 9-(?-d-arabinofuranosyl)adenine 2′,5′-cyclic monophosphate (2′,5′-ara-cAMP, 2) in D2O solution is described. The sugar-ring conformations in 1 and 2 are shown to be 3E and 2E, respectively, and the phosphate rings are in a chair form. An unusual 4JP,H coupling of 2.4 Hz is observed between H-4′ and phosphorus in 1 and a vicinal JP,H of 30.8 Hz between H-5′ and phosphorus in 2. This latter coupling verifies a similar value found previously in the ara-cytidine analog of 2. A comparison of the conformational properties of cyclic nucleotides having fused phosphate and sugar rings has been made, together with an assessment of the use of the Karplus constants in such ring-systems. 相似文献
12.
6-Methylpurine (MeP) is cytotoxic adenine analog that does not exhibit selectivity when administered systemically, and could be very useful in a gene therapy approach to cancer treatment involving Escherichia coli PNP. The prototype MeP releasing prodrug, 9-(β-d-ribofuranosyl)-6-methylpurine, MeP-dR has demonstrated good activity against tumors expressing E. coli PNP, but its antitumor activity is limited due to toxicity resulting from the generation of MeP from gut bacteria. Therefore, we have embarked on a medicinal chemistry program to identify non-toxic MeP prodrugs that could be used in conjunction with E. coli PNP. In this work, we report on the synthesis of 9-(6-deoxy-β-d-allofuranosyl)-6-methylpurine (3) and 9-(6-deoxy-5-C-methyl-β-d-ribo-hexofuranosyl)-6-methylpurine (4), and the evaluation of their substrate activity with several phosphorylases. The glycosyl donors; 1,2-di-O-acetyl-3,5-di-O-benzyl-α-d-allofuranose (10) and 1-O-acetyl-3-O-benzyl-2,5-di-O-benzoyl-6-deoxy-5-C-methyl-β-d-ribohexofuran-ose (15) were prepared from 1,2:5,6-di-O-isopropylidine-α-d-glucofuranose in 9 and 11 steps, respectively. Coupling of 10 and 15 with silylated 6-methylpurine under Vorbrüggen glycosylation conditions followed conventional deprotection of the hydroxyl groups furnished 5′-C-methylated-6-methylpurine nucleosides 3 and 4, respectively. Unlike 9-(6-deoxy-α-l-talo-furanosyl)-6-methylpurine, which showed good substrate activity with E. coli PNP mutant (M64V), the β-d-allo-furanosyl derivative 3 and the 5′-di-C-methyl derivative 4 were poor substrates for all tested glycosidic bond cleavage enzymes. 相似文献
13.
Yun-Seo Kil Jiyoung Park Mahtab Jafari Hyun Ae Woo Eun Kyoung Seo 《Bioorganic & medicinal chemistry letters》2017,27(14):3065-3070
A new coumarin, (?)-cis-(3′R,4′R)-4′-O-angeloylkhellactone-3′-O-β-d-glucopyranoside (1) and two new chalcones, 3′-[(2E)-5-carboxy-3-methyl-2-pentenyl]-4,2′,4′-trihydroxychalcone (4) and (±)-4,2′,4′-trihydroxy-3′-{2-hydroxy-2-[tetrahydro-2-methyl-5-(1-methylethenyl)-2-furanyl]ethyl}chalcone (5) were isolated from the aerial parts of Angelica keiskei (Umbelliferae), together with six known compounds: (R)-O-isobutyroyllomatin (2), 3′-O-methylvaginol (3), (?)-jejuchalcone F (6), isoliquiritigenin (7), davidigenin (8), and (±)-liquiritigenin (9). The structures of the new compounds were determined by interpretation of their spectroscopic data including 1D and 2D NMR data. All known compounds (2, 3, and 6–9) were isolated as constituents of A. keiskei for the first time. To identify novel hepatocyte proliferation inducer for liver regeneration, 1–9 were evaluated for their cell proliferative effects using a Hep3B human hepatoma cell line. All isolates exhibited cell proliferative effects compared to untreated control (DMSO). Cytoprotective effects against oxidative stress induced by glucose oxidase were also examined on Hep3B cells and mouse fibroblast NIH3T3 cells and all compounds showed significant dose-dependent protection against oxidative stress. 相似文献
14.
Saúl Martínez-Montero Susana Fernández Yogesh S. Sanghvi Emmanuel A. Theodorakis Mervi A. Detorio Tamara R. Mcbrayer Tony Whitaker Raymond F. Schinazi Vicente Gotor Miguel Ferrero 《Bioorganic & medicinal chemistry》2012,20(23):6885-6893
A series of 2′,3′-dideoxy-2′,2′-difluoro-4′-azanucleosides of both pyrimidine and purine nucleobases were synthesized in an efficient manner starting from commercially available L-pyroglutamic acid via glycosylation of difluorinated pyrrolidine derivative 15. Several 4′-azanucleosides were prepared as a separable mixture of α- and β-anomers. The 6-chloropurine analogue was obtained as a mixture of N7 and N9 regioisomers and their structures were identified based on NOESY and HMBC spectral data. Among the 4′-azanucleosides tested as HIV-1 inhibitors in primary human lymphocytes, four compounds showed modest activity and the 5-fluorouracil analogue (18d) was found to be the most active compound (EC50 = 36.9 μM) in this series. None of the compounds synthesized in this study demonstrated anti-HCV activity. 相似文献
15.
Naveen C. Srivastav Neeraj Shakya Michelle Mak Chao Liang D. Lorne J. Tyrrell Babita Agrawal Rakesh Kumar 《Bioorganic & medicinal chemistry》2010,18(21):7542-7547
Chronic infections with hepatitis B virus (HBV) and hepatitis C virus (HCV) lead to serious liver diseases worldwide. Co-infection with HBV and HCV is very common and is associated with increased risk of liver pathogenesis, liver cancer, and liver failure. Several 5-substituted 3′-fluoro (or chloro) (1–4, 6, 7, 17–19) and 2′,3′-difluoro 2′,3′-dideoxynucleosides (15 and 16) were synthesized and evaluated for in vitro antiviral activities against duck hepatitis B virus (DHBV), human hepatitis B virus, and hepatitis C virus. Of these compounds 4, 7, 17, and 19 demonstrated moderate anti-HBV activity, and 2, 4, 7, 8, and 19 were weak inhibitors of HCV. Although 5-iodo derivative (7) was most inhibitory against HCV, it exhibited a reduction in cellular RNA levels in Huh-7 cells. The 5-hydroxymethyl-3′-fluoro-2′,3′-dideoxyuridine (4) and 1-(3-chloro-2,3-dideoxy-β-d-erythro-pentofuranosyl)-5-fluorouracil (19) provided the most inhibition of both viruses without cytotoxicity. 相似文献
16.
Adenosine-5′-carboxaldehyde (1a) was treated with nitromethane under alkaline conditions, to give the two stereoisomeric 5′-C-(nitromethyl) derivatives (2 and 3) of adenosine. Catalytic hydrogenation of 2 gave 9-(6-amino-6-deoxy-β-D-allofuranosyl)adenine (4), which, on treatment with nitrous acid, yielded 9-(β-D-allofuranosyl)hypoxanthine (6). Similar treatment of 3 gave the α-L-talo nucleosides 5 and 7. Reaction of 2′,3′-O-p-anisylidene adenosine-5′-carboxaldehyde (1b) with ethoxycarbonylmethylene-triphenylphosphorane afforded 9-(ethyl 5,6-dideoxy-β-D- ribo-hept-5-enofuranosyluronate)adenine (8), which was hydrolyzed to the corresponding uronic acid (9). Catalytic hydrogenation of 8 gave 9-(ethyl 5,6-dideoxy-β-D-ribo-heptofuranosyluronate)adenine (10). Reduction of 8 with lithium aluminum hydride yielded two new analogs of adenosine: 9-(5,6-dideoxy-β-D-ribo-heptofuranosyl)adenine (12) and 9-(5,6-dideoxy-β-D-ribo-hept-5-enofuranosyl)adenine (13). 相似文献
17.
Yerra Koteswara Rao Shih-Hua Fang Yew-Min Tzeng 《Bioorganic & medicinal chemistry》2009,17(23):7909-7914
A series of 23 3′,4′,5′-trimethoxychalcone analogues was synthesized and their inhibitory effects on nitric oxide (NO) production in LPS/IFN-γ-treated macrophages, and tumor cell proliferation has been investigated. 4-Hydroxy-3,3′,4′,5′-tetramethoxychalcone (7), 3,4-dihydroxy-3′,4′,5′-trimethoxychalcone (11), 3-hydroxy-3′,4,4′,5′-tetramethoxychalcone (14), and 3,3′,4′,5′-tetramethoxychalcone (15) were the most potent growth inhibitory agents on NO production, with an IC50 value of 0.3, 1.5, 1.3 and 0.3 μM, respectively. The tumor cells proliferation assay results revealed that several compounds exhibited potent inhibition activity against different cancer cell lines. The chalcone 15 was the most potent anti-proliferative compound in the series with IC50 values of 1.8 and 2.2 μM toward liver cancer Hep G2 and colon cancer Colon 205 cell lines, respectively. 2,3,3′,4′,5′-Pentamethoxychalcone (1), 3,3′,4,4′,5,5′-hexamethoxychalcone (3), 2,3′,4,4′,5,5′-hexamethoxychalcone (5), 2-hydroxy-3,3′,4′,5′-tetramethoxychalcone (10), 11 and 14 showed significant anti-proliferation actions in Hep G2 and Colon 205 cells with an IC50 values ranging between 10 and 20 μM. Among the tested agents, compound 7 showed selective NO production inhibition (IC50 = 0.3 μM), while has no effect on tumor cell proliferation (IC50 >100 μM). 3,3′,4,4′,5′-Pentamethoxychalcone (2) showed selective anti-proliferation effect in Hep G2 cells, in addition to its potent NO inhibition, however has no such response in Colon 205 cells. In contrast, 3-formyl-3′,4′,5′-trimethoxychalcone (22) showed moderate growth inhibition in Colon 205 cells, while has no such effect on NO production and Hep G2 cells proliferation. These results provide insight into the correlation between some structural properties of 3′,4′,5′-trimethoxychalcones and their in vitro anti-inflammatory and anti-cancer differentiation activity. 相似文献
18.
Shi-Qing Xu Xin Yan Ying Chen Peng Xia Keduo Qian Donglei Yu Yi Xia Zheng-Yu Yang Susan L. Morris-Natschke Kuo-Hsiung Lee 《Bioorganic & medicinal chemistry》2010,18(20):7203-7211
In a continuing investigation into the pharmacophores and structure–activity relationship (SAR) of (3′R,4′R)-3′,4′-di-O-(S)-camphanoyl-(+)-cis-khellactone (DCK) as a potent anti-HIV agent, 2′-monomethyl substituted 1′-oxa, 1′-thia, 1′-sulfoxide, and 1′-sulfone analogs were synthesized and evaluated for inhibition of HIV-1 replication in H9 lymphocytes. Among them, 2′S-monomethyl-4-methyl DCK (5a)3 and 2′S-monomethyl-1′-thia-4-methyl DCK (7a) exhibited potent anti-HIV activity with EC50 values of 40.2 and 39.1 nM and remarkable therapeutic indexes of 705 and 1000, respectively, which were better than those of the lead compound DCK in the same assay. In contrast, the corresponding isomeric 2′R-monomethyl-4-methyl DCK (6) and 2′R-monomethyl-1′-thia-4-methyl DCK (8) showed much weaker inhibitory activity against HIV-1 replication. Therefore, the bioassay results suggest that the spatial orientation of the 2′-methyl group in DCK analogs can have important effects on anti-HIV activity of this compound class. 相似文献
19.
Mingzhang Gao Min Wang Qi-Huang Zheng 《Bioorganic & medicinal chemistry letters》2018,28(13):2234-2238
The reference standards methyl 3-((2,2-difluoro-5H-[1,3]dioxolo[4′,5′:4,5]benzo[1,2-d]imidazol-6-yl)carbamoyl)benzoate (5a) and N-(2,2-difluoro-5H-[1,3]dioxolo[4′,5′:4,5]benzo[1,2-d]imidazol-6-yl)-3-methoxybenzamide (5c), and their corresponding desmethylated precursors 3-((2,2-difluoro-5H-[1,3]dioxolo[4′,5′:4,5]benzo[1,2-d]imidazol-6-yl)carbamoyl)benzoic acid (6a) and N-(2,2-difluoro-5H-[1,3]dioxolo[4′,5′:4,5]benzo[1,2-d]imidazol-6-yl)-3-hydroxybenzamide (6b), were synthesized from 5-amino-2,2-difluoro-1,3-benzodioxole and 3-substituted benzoic acids in 5 and 6 steps with 33% and 11%, 30% and 7% overall chemical yield, respectively. Carbon-11-labeled casein kinase 1 (CK1) inhibitors, [11C]methyl 3-((2,2-difluoro-5H-[1,3]dioxolo[4′,5′:4,5]benzo[1,2-d]imidazol-6-yl)carbamoyl)benzoate ([11C]5a) and N-(2,2-difluoro-5H-[1,3]dioxolo[4′,5′:4,5]benzo[1,2-d]imidazol-6-yl)-3-[11C]methoxybenzamide ([11C]5c), were prepared from their O-desmethylated precursor 6a or 6b with [11C]CH3OTf through O-[11C]methylation and isolated by HPLC combined with SPE in 40–45% radiochemical yield, based on [11C]CO2 and decay corrected to end of bombardment (EOB). The radiochemical purity was >99%, and the molar activity (MA) at EOB was 370–740?GBq/μmol with a total synthesis time of ~40-min from EOB. 相似文献
20.
Three new aromatic compounds, identified as 1-(3′,4′-methylenedioxy-phenyl)-10-(3″-hydroxyphenyl)-decane (1), 1-(3′,4′-methylenedioxy-phenyl)-12-(3″-hydroxyphenyl)-dodecane (2), and 1-(3′,4′-methylenedioxy-phenyl)-12-(3″-hydroxyphenyl)-6Z-dodecylene (3), along with six known compounds (4–9) were isolated from the 95% EtOH extract of Homalomena occulta. Their structures were elucidated by chemical and spectral methods Compounds 4–9 were isolated for the first time from this plant. Compounds 1–3 exhibited inhibitory activity against BACE1, with IC50 values of 0.82–1.09 μmol/L. 相似文献