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1.
Claisen-Schmidt condensation of 3-(1,2,3,6-tetrahydro-1-methylpyridin-4-yl)-2,4,5- trimethoxybenzaldehyde 3 and various aromatic, heterocyclic and alicyclic amides of 3- aminoacetophenone 6(a–s) afforded novel curcumin mimics. All the synthesized compounds were characterized by IR, 1H NMR, Mass spectroscopy and evaluated for antioxidant, cytotoxicity and antimicrobial activity. Out of the 20 compounds screened, compounds 7i, 7l, 7q, and 7n have shown excellent radical scavenging activity, compounds 7o, 7t, 7f, and 7r have shown significant xanthine oxidase inhibition, and compounds 7a, 7k and 7l were found to be potent inhibitors of selected cancer cell lines. Compounds 7h, 7t, 7l, 7i, and 7e have shown good antibacterial activity, whereas compounds 7j, 7f, 7o, 7h, and 7t exhibited significant antifungal activity.  相似文献   

2.

Synthesis of 2,2,3-tris(hydroxymethyl)methylenecyclopropane analogues 16a, 16b, 17a, and 17b is described. Diethyl ester of Feist's acid 18b was hydroxymethylated via carbanion formation using formaldehyde under simultaneous isomerization to cis diester to give intermediate 19. Reduction followed by acetylation gave triacetate 22. Addition of bromine afforded reagent 23, which was used for alkylation-elimination of adenine and 2-amino-6-chloropurine to provide Z,E-isomeric mixtures of 24a and 24b. Deacetylation and separation furnished the Z-isomers 16a, 16c and E-isomers 17a, 17c. Hydrolytic dechlorination of 16c and 17c gave guanine analogues 16b and 17b. None of the analogues exhibited a significant antiviral activity. Adenosine deaminase is refractory toward adenine analogues 16a and 17a.  相似文献   

3.
5-Acetyl-2-aryl-6-methyl-4-(2,3,4,6-tetra- O -acetyl-β-D-glucopyranosylmercapto)pyramidines 3a–c were obtained by the reaction of 5-acetyl-2-aryl-6-methyl-pyrimidine thiol 1a–c with 2,3,4,6-tetra- O -acetyl-α-D-glucopyranosyl bromide (2) in aq. KOH/acetone. The reaction of 1a–c with peracetylated galactose 5 and peracetylated ribose 8 under MW irradiation gave 5-acetyl-2-aryl-6-methyl-4-(2,3,4,6-tetra- O -acetyl-β-D-galactopyranosylmercapto)pyrimidine 6a–c and 5-acetyl-2-aryl-6-methyl-4-(2,3,5-tri- O -acetyl-β-D-ribofuranosylmercapto)pyrimidines 9a–c. The deprotection of 3a–c, 6a–c, and 9a–c in the presence of methanol and TEA/H2O yielded the deprotected products 4a–c, 7a–c, and 10a–c. The structures of the compounds were confirmed by using IR, 1H, 13C spectra and microanalysis. Selected members of these compounds were screened for antimicrobial activity.  相似文献   

4.
海南石斛化学成分研究   总被引:1,自引:0,他引:1  
为了解海南石斛(Dendrobium hainanense Rolfe)的化学成分,采用色谱技术从海南石斛茎叶中分离得到14个化合物,经波谱分析分别鉴定为:2,6-二甲氧基对苯醌(1)、(+)-dehydrovomifoliol(2)、blumenol A(3)、2,7-二羟基-3,4-二甲氧基-9,10-二氢菲(4)、2,7-二羟基-3,4-二甲氧基菲(5)、3,7-二羟基-2,4-二甲氧基菲(6)、3-羟基-2,4,7-三甲氧基-9,10-二氢菲(7)、3-羟基-2,4,7-三甲氧基菲(8)、3,4,7-三羟基-2-甲氧基菲(9)、3,7-二羟基-2,4-二甲氧基-9,10-二氢菲(10)、(+)-lyoniresinol(11)、丁香脂素(12)、denchrysan A(13)和nobilone(14)。这些化合物均为首次从海南石斛中分离得到。活性测试结果表明化合物4~6、8~9、11和14对乙酰胆碱酯酶有抑制活性。  相似文献   

5.
Abstract

This article describes the synthesis of some novel heterocyclic sulfonamides having biologically active thiophene 3, 4, 5, 6, coumarin 8, benzocoumarin 9, thiazole 7, piperidine 10, pyrrolidine 11, pyrazole 14 and pyridine 12, 13. Starting with 4-(1-(2-(2-cyanoacetyl)hydrazono)ethyl)-N-ethyl-N-methylbenzenesulfonamide (2), which was prepared from condensation of acetophenone derivative 1 with 2-cyanoacetohydrazide. The structures of the newly synthesized compounds were confirmed by elemental analysis, IR, 1H NMR, 13C NMR, 19F NMR and MS spectral data. All the newly synthesized heterocyclic sulfonamides were evaluated as in-vitro anti-breast cancer cell line (MCF7) and as in-vitro antimicrobial agents. Compounds 8, 5 and 11 were more active than MTX reference drug and compounds 12, 7, 4, 14, 5 and 8 were highly potent against Klebsiella pneumonia. Molecular operating environment performed virtual screening using molecular docking studies of the synthesized compounds. The results indicated that some prepared compounds are suitable inhibitor against dihydrofolate reductase (DHFR) enzyme (PDBSD:4DFR) with further modification.  相似文献   

6.

The Z- and E-thymine and cytosine pronucleotides 3d, 4d, 3e, and 4e of methylenecyclopropane nucleosides analogues were synthesized, evaluated for their antiviral activity against human cytomegalovirus (HCMV), herpes simplex virus 1 and 2 (HSV-1 and HSV-2), varicella zoster virus (VZV), Epstein-Barr virus (EBV), human immunodeficiency virus type 1 (HSV-1), and hepatitis B virus (HBV) and their potency was compared with the parent compounds 1d, 2d, 1e, and 2e. Prodrugs 3d and 4d were obtained by phosphorylation of parent analogues 1d or 2d with reagent 8. A similar phosphorylation of N4-benzoylcytosine methylenecyclopropanes 9a and 9b gave intermediates 11a and 11b. Deprotection with hydrazine in pyridine–acetic acid gave pronucleotides 3e and 4e. The Z-cytosine analogue 3e was active against HCMV and EBV. The cytosine E-isomer 4e was moderately effective against EBV.  相似文献   

7.
为了解油榄仁(Terminalia bellirica Roxb.)的化学成分,从油榄仁果实的乙酸乙酯提取物中分离得到11个化合物,通过波谱分析,分别鉴定为:表松脂酚(1)、(–)-芝麻素(2)、麻醉椒苦素(3)、二氢醉椒素(4)、异香兰素(5)、3,4-二羟基苯甲酸(6)、没食子酸(7)、没食子酸甲酯(8)、没食子酸乙酯(9)、3,4,8,9,10-五羟基二苯骈[b,d]吡喃-6-酮(10)、polystachyol(11),其中化合物1~6、10和11为首次从油榄仁果实中分离得到。  相似文献   

8.
Abstract

The synthesis of monomers ( S )-1, ( R )-1 and 2 derived from (5′ S )-, (5′ R )-2′-deoxythymidine-5′-C-phosphonic acids and 2′,5′-dideoxythymidine-5′-C-phosphonic acids was elaborated. The protection of the 5′-hydroxyl by the methoxycarbonyl group was a key step of the synthesis. Prepared monomers were used for the solid-phase assembly of several types oligothymidylate 15-mers ( S )-3, ( S )-4, ( S )-5, ( R )-4 and ( R )-5 containing the chiral 3′-O-P-CH(OH)-5″ internucleotide linkage. Their hybridization properties with dA15 and rA15 were studied as well as their resistance against nuclease cleavage.  相似文献   

9.
The intranasal route is one of the main routes of Mycobacterium leprae infection and there is paucity of information regarding the mode of spread of the pattern. The adherence of M.leprae to the nasal mucosa, its trapping within the sinuses of the head, and its fate after entry into the host was studied using mouse model. A comparison of the adherence profile of M. leprae and Mycobacterium tuberculosis showed that while larger numbers of M. tuberculosis were demonstrated within lungs, greater numbers of M.leprae were present within the sinuses of the head. Adherence of M.leprae to the nasal mucosa was dependent on surface integrity since opsonization and heat killing resulted in decreased numbers of M.leprae in the nasal sinuses and a greater amount entering the lungs. The adherence appeared to the independent of the viability of the bacilli, as similar numbers of formalin-fixed, rifampicin-treated and viable M.leprae entered the lungs in the initial stages. However the numbers of rifampicin-treated M. leprae in the nasal sinuses were 12-fold lower than the numbers of viable M.leprae. These results indicated that both viability and surface integrity were important in the entry of M.leprae and it’s consequent dissemination.  相似文献   

10.
Alansmia, a new genus of grammitid ferns is described and combinations are made for the 26 species known to belong to it. Alansmia is supported by five morphological synapomorphies: setae present on the rhizomes, cells of the rhizome scales turgid, both surfaces of the rhizome scales ciliate, laminae membranaceous, and sporangial capsules setose. Other diagnostic characters include pendent fronds with indeterminate growth, concolorous, orange to castaneous rhizome scales with ciliate or sometimes glandular margins, hydathodes often cretaceous, and setae simple, paired or stellate. The group also exhibits the uncommon characteristic of producing both trilete and apparently monolete spores, sometimes on the same plant. New combinations are made for Alansmia alfaroi, A. bradeana, A. canescens, A. concinna, A. contacta, A. cultrata, A. dependens, A. diaphana, A. elastica, A. glandulifera, A. heteromorpha, A. immixta, A. kirkii, A. lanigera, A. laxa, A. longa, A. monosora, A. reclinata, A. semilunaris, A. senilis, A. smithii, A. spathulata, A. stella var. stella, A. stella var. flava, A. turrialbae, A. variabilis, A. xanthotrichia. Lectotypifications are made for Alansmia concina, A. variabilis, Polypodium ciliare, P. flexile, and P. ovalescens. The genus is named in honor of pteridologist Alan R. Smith.  相似文献   

11.
A series of novel carbazole chalcones has been synthesised and evaluated for radical scavenging activity, cytotoxicity and antimicrobial activities. Compounds 12m, 12o and 12c exhibited good 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, compounds 12e, 12m and 12d were excellent hydroxyl radical scavengers and compounds 12a, 12e, 12g, 12n and 12m have shown inhibition of oxidative DNA damage induced by 2,2′-azobis (2-amidinopropane hydrochloride). Compounds 12j, 12i, 12n, 12c, 12m and 12e were most active against the selected cancer cell lines. Compounds 12a, 12e and 12m showed good antibacterial activity and compounds 12h and 12m have shown good antifungal activity. All the compounds were subjected for absorption, distribution, metabolism and excretion (ADME) predictions by computational method and found that these molecules could be considered as potential candidates for oral drug development.  相似文献   

12.
Fifteen steroidal saponins 115, which include 4 furostanol glycosides 13 and 15, and 11 spirostanol glycosides 414, were isolated from the tubers and leaves of lesser yam (Dioscorea esculenta, Togedokoro). Their structures were identified by nuclear magnetic resonance and liquid chromatography mass spectroscopy. Four steroidal saponins 9, 11, 14, and 15 were found to be novel compounds.  相似文献   

13.
Rubralactone (1), rubralides A, B and C (24), rubramin (5), and 2-formyl-3,5-dihydroxy-4-methylbenzoic acid (6), were isolated from Penicillium rubrum, and their structures established by spectroscopic methods including 2D NMR. The effects on plant growth of 16 were examined using the lettuce seedling bioassay. Compound 1 promoted root growth. Compounds 2, 3 and 5 inhibited the growth of lettuce seedlings, but 4 and 6 did not have any inhibitory effect on their growth.  相似文献   

14.
A. A. Kotov 《Hydrobiologia》1996,341(3):187-196
We investigated the morphology of adult and juvenile stages of females and males of Bosmina longispina Leydig from a North Icelandic population. There are additional setae near the basis of the second antenna and between its branches in adult males, not described in Bosmina, but known from other Anomopoda. New features of female morphology are also found. The development of the first limb and postabdomen of the male is described in detail. In juvenile males of B. longispina (belonging to subgenus Eubosmina), characteristics of morphology, similar to those in adult males of other subgenera are found.Abbreviations af antennal flap - as additional setae of male - bs basis of seta of clasper - bc basis of postabdominal claws - ch clasper hook - cl clasper - cs seta of clasper - cw claws of postabdomen - de distal endite of the first limb - dr dorsal row of denticles on male postabdomen - df dorsal fold of carapace - eh ejector hooks of limb I - ep epipodite - ex exopodite - fp frontal head pore - fs frontal seta - hs hair sensilla - in incision of juvenile male postabdomen - ir interrupted rows of setules on postabdomen - Ip lateral head pore - mp median head pore - mpr maxillar process of limb I - mr main row of denticles on postabdominal claws - pe predistal endite of limb I - pf preantennal fold of valve - pl plate above postabdominal setae - ps postabdominal setae - rs rudimentary setae - sr second row of denticles near basis of claws - vf ventral fold of valve - vr ventral row of denticles on male postabdomen  相似文献   

15.
Conferin (1), a new isoflavone, has been isolated from the ethyl acetate soluble fraction of Caragana conferta Benth. along with seven known compounds, namely biochanin A (2), p-hydroxybenzoic acid (3), 3,5- dimethoxybenzoic acid (4), ursolic acid (5), erythrodiol (6), pinoresinol (7), and syringresinol (8), reported for the first time from this species. The structure of the new isoflavone was deduced on the basis of spectroscopic studies. Compounds 1 and 2 were investigated for biological activities and showed significant anti-inflammatory activity in carrageenan induced paw edema of rats. Evaluation of antioxidant activity by the radical scavenging method indicated that compound 1 is a potent antioxidant while 2 is moderately active. It was also shown that the reducing capability of compound 2 was remarkably increased in a concentration dependent manner as compared to 1. Compound 1 showed moderate inhibitory activity against the enzyme lipoxygenase, while 2 showed weak activity.  相似文献   

16.
为了解苦槛蓝(Myoporum bontioides)的化学成分,采用色谱分离法从叶中分离得到11个化合物,分别鉴定为:5, 7, 3?-三羟基-4?-甲氧基黄酮(1)、3, 5, 7, 4?-四羟基-3?-甲氧基黄酮(2)、5, 7, 4?-三羟基-3?, 5?-二甲氧基黄酮(3)、木犀草素(4)、山奈酚(5)、鼠李黄素(6)、5, 7-二羟基二氢黄酮(7)、7, 4?-二羟基二氢黄酮(8)、5, 7, 3?, 4?-四羟基二氢黄酮(9)、5-O-乙酰基-3, 7, 3?, 4?-四羟基二氢黄酮(10)和7-甲氧基香橙素(11)。除化合物4711之外,其他化合物均为首次从苦槛蓝叶中分离得到。菌丝生长速率法测试表明化合物47~911对荔枝霜疫霉菌具有较好的抑菌活性。  相似文献   

17.
Regioselective alkylation of 5-(3-chlorobenzo[b]thien-2-yl)-4H-1,2,4-triazole (1) with hydroxy alkylating agents 2, 3, 13, and the 2,3-O-isopropylidene-1-O-(p-tolylsulfonyl)-glycerol (10) afforded the corresponding S-alkylated derivatives 6, 7, 11, and 14 under both conventional and microwave irradiation conditions; bentonite as a solid support gave better results, with no change in regioselectivity. A facile intramolecular dehydrative ring closure of 6, 7, 11, and 14 using K2CO3 in DMF afforded the corresponding fused triazolo-thiazines and thiazolo-triazole 17–19. The isopropylidenes and acetyl derivatives of the products were prepared.  相似文献   

18.
The 3-deoxy-3-fluoro-6-S-(2-S-pyridyl)-6-thio-β-d-glucopyranosyl nucleoside analogs 7 were prepared via two facile synthetic routes. Their precursors, 3-fluoro-6-thio-glucopyranosyl nucleosides 5a-e, were obtained by the sequence of deacetylation of 3-deoxy-3-fluoro-β-d-glucopyranosyl nucleosides 2a-e, selective tosylation of the primary OH of 3 and finally treatment with potassium thioacetate. The desired thiolpyridine protected analogs 7a-c,f,g were obtained by the sequence of deacetylation of 5a-c followed by thiopyridinylation and/or condensation of the corresponding heterocyclic bases with the newly synthesized peracetylated 6-S-(2-S-pyridyl) sugar precursor 13, which was obtained via a novel synthetic route from glycosyl donor 12. None of the compounds 6 and 7 showed antiviral activity, but the 5-fluorouracil derivative 7c and particularly the uracil derivative 7b were endowed with an interesting and selective cytostatic action against a variety of murine and human tumor cell cultures.  相似文献   

19.
A chemical investigation of Digitalis purpurea seeds led to the isolation of three new cardenolide glycosides (1, 8 and 11), together with 12 known cardenolide glycosides (27, 9, 10 and 1215). The structures of 1, 8 and 11 were determined by 1D and 2D NMR spectroscopic analyses and the results of an acid or enzymatic hydrolysis. The cytotoxic activity of the isolated compounds (115) against HL-60 leukemia cells was examined. Compounds 2, 9, 11 and 12 showed potent cytotoxicity against HL-60 cells with respective 50% inhibition concentration (IC50) values of 0.060, 0.069, 0.038, and 0.034 µM. Compounds 2, 9 and 11 also exhibited potent cytotoxic activity against HepG2 human liver cancer cells with respective IC50 values of 0.38, 0.79, and 0.71 µM. An investigation of the structure-activity relationship showed that the cytotoxic activity was reduced by the introduction of a hydroxy group at C-16 of the digitoxigenin aglycone, methylation of the C-3' hydroxy group at the fucopyranosyl moiety, and acetylation of the C-3' hydroxy group at the digitoxopyranoyl moiety.  相似文献   

20.
Noel H. Holmgren 《Brittonia》1992,44(4):481-482
Combinations are made forKeckiella antirrhinoides var.microphylla, K. rothrockii var.jacintensis, K. ternata var.septentrionalis, Penstemon fruticiformis var.amargosae, P. grinnellii var.scrophularioides, P. heterodoxus var.cephalophorus, P. heterodoxus var.shastensis, andP. newberryi var.berryi.  相似文献   

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