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1.
Twenty-seven compounds including nine triterpenoids (19), eight sterols (1017), two ribonucleotides (18, 19), four phenols (2023), three glycosides (2426), and one furan (27) were isolated from the fruiting bodies of Trametes versicolor (L.) Lloyd. This study is the first confirmation of the presence of the 11 compounds (3, 5, 6, 8, 18, 20, 21, 2325, and 27) isolated from the Polyporaceae family, with six of these (2 and 1216) from the genus Trametes. Compounds 3, 4, 10, 11, 16 and 17 were found to significantly inhibit the production of NO, TNF-α and IL-6 in a dose-dependent manner.  相似文献   

2.

Friedel-Crafts acyl rearrangements in PPA of diacetylpyrenes (80–120 °C), dibenzoylpyrenes (80–200 °C), and bis(4-flurobenzoyl)pyrenes (80–120 °C) and Scholl reactions in AlCl3/NaCl of dibenzoylpyrenes (140–200 °C) have been studied. The substrates were 1-AcPY, 2-AcPY, 1,3-Ac2PY, 1,6-Ac2PY, 1,8-Ac2PY2,7-Ac2PY, 1-BzPY, 1,6-Bz2PY, 1,8-Bz2PY, 1-4FBzPY, 1,6-4FBz2PY, 1,8-4FBz2PY. The mixtures of pyrene, 1-AcPY, 2-AcPY, 1,3-Ac2PY, 1,6-Ac2PY, 1,8-Ac2PY, and 2,7-Ac2PY were separated by HPLC. The following reversible intermolecular isomerizations were established: 1,6-Ac2PY ? 1,8-Ac2PY, 1,6-Bz2PY ? 1,8-Bz2PY, and 1,6-4'FBz2PY ? 1,8-4'FBz2PY, albeit not in high yields. The results substantiate Gore’s 1955 proposition that “The Friedel–Crafts acylation reaction of reactive aromatic hydrocarbons is a reversible process.” The isomerizations reported here differ from the few previously reported completely reversible intramolecular Friedel-Crafts acyl rearrangements. At ≥ 140 °C, in PPA and in AlCl3/NaCl, 1,6-Bz2PY and 1,8-Bz2PY underwent a highly regioselective double Scholl reaction to give pyranthrone (3) and deacylations to 1-BzPy (and pyrene), followed by mono-Scholl reactions to give 8H-dibenzo[def,qr]chrysen-8-one (1), and 11H-indeno[2,1-a]pyren-11-one (2). The formation of 3 and not the expected tribenzo[a,ghi,o]perylene-7,16-dione (4) from 1,8-Bz2PY indicates that 1,8-Bz2PY has first undergone isomerization to 1,6-Bz2PY. The present study confirms the linkage between Friedel-Crafts acyl rearrangements and the Scholl reaction.

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3.
The pentacyclic lactams9,11, and14 were prepared using a thermal condensation of tryptamine with symmetrical oxodiesters3 and4 as the key step. The formation of the ring E in the tetracyclic compounds5,6,8,10,12, and13 is strongly dependent on the ring size.
Synthese von Analoga der Canthin/Erythrina Alkaloide (Kurze Mitteilung)
Zusammenfassung Die pentacyclischen Verbindungen9,11 und14 wurden durch thermische Kondensation von Tryptamin mit symmetrischen Oxodiestern3 und4 als wichtigster Reaktionsstufe dargestellt. Die Bildung des Ringes E in den tetracyclischen Verbindungen5,6,8,10,12 und13 ist stark von der Ringgröße abhängig.
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4.
Stable configurations of XC3H3Si five-membered rings, 1 X and 2 X (X = CH, N, P, and As) in the singlet and triplet states are found at B3LYP/6-311++G** level of theory. All the singlet states of 1 X and 2 X have lower potential energy than the triplet state. The ΔG s−t differences between the singlet and triplet states of 1 X and 2 X changes at the B3LYP/6-311++G** level in the order (in kcal/mol): 1 N (−17.56) > 1 CH (−15.26) > 1 P (−4.96) > 1 As (−3.45) and 2 CH (−15.26) > 2 N (−9.21) > 2 P (−7.39) > 2 As (−6.15), respectively.  相似文献   

5.
Selective methods for the incorporation of stable isotopes 15N and 2H into the structure of antiviral medicine “triazavirine” 1 were developed. The synthesized isotopically modified “triazavirine” 1 2 H 3 , 15 N 3 contained the labeled atoms in both the azole and the azine rings. 13C and 15N NMR spectra of the isotope-containing sample 1 2 H 3 , 15 N 3 were thoroughly analyzed.  相似文献   

6.
Reaction of 4‐aryl‐1‐thioxo [1,2,4] triazolo [4,3‐a] quinazolin‐5 (4H)‐ones (2a,b) with acetylated glycosyl bromides 3ac under alkaline conditions afforded the corresponding S‐glycoside derivatives 4, 5 and N‐glycoside derivatives 6, 7. Oxidation of S‐glycosyl derivatives 4, 5 with m‐chloroperbenzoic acid yielded the corresponding sulphones 8, 9, whereas the N‐glycosyl derivatives 6, 7 yielded 1‐oxo derivatives 10, 11. However their O‐deacetylation with sodium methoxide in methanol caused cleavage of the S‐glycosyl residue and gave N 2‐glycosylated analogues 12, 13, 14 and 15.  相似文献   

7.
Compound 3 and 5a, b were obtained from the reaction of 1,3,4,4-tetrachloro-1-thioallyl-2-nitro-1,3-butadiene (1) with thiomorpholine (2) and piperazine derivatives 4a, b in dichloromethane. The reaction of compound 1 and bromine gave compound 6. Compounds 8 and 10 were obtained from the reaction of 6 with 1-(diphenylmethyl)piperazine (7) and piperidine (9) in dichloromethane. The derivative 13 was synthesized from the reaction of 4-bromo-1,1,3,4-tetrachloro-2-nitro-1,3-butadiene (11) and allylmercaptane (12). Compounds 15 and 16a, b were obtained from the reaction of 1-allyl-4-bromo-1,3,4-trichloro-2-nitro-1,3-butadiene (13) with morpholine (14) and the piperazine derivatives 16a, b, in dichloromethane, respectively.  相似文献   

8.
Abstract

The terephthalic acid hydrazide(1) reacted with phenyl/benzyl isothiocyanate2a,bto yield the corresponding bis-thiosemicarbazides4a,b,viaacid hydrolysis of the intermediate 3whereas cyclization of4gave the bis-1,2,4-triazoles 5,6and bis-1,3,4-thiadiazoles7,8. Similarly, compound 1reacted with phenyl isocyanate9to give the bis-semicarbazide10, which was cyclized to the bis-oxadiazole 11and/or bis-1,2,4-triazole12in POClti3and NaOH respectively.  相似文献   

9.
The reaction of Lawesson's reagent 1a, with niclosamide 2 proceeded by thionation and formation of carbothioamide 3 and the zwitterionic oxathiaphosphinin 4a. LR reacted with 8-hydroxyquinoline (5), 2-methylquinoline-4-ol (7), and β-naphthol (9) to give the phosphonodithioates 6, 8, or 10. The reaction of LR with the Mannich bases 11 and 14 afforded the oxathiaphosphinins 13 and 15, whereas the phosphonodithioates 17 and 19 were isolated in the case of Mannich bases 16 and 18. LR reacted with phthalimide Mannich base 20 to give the dithione 21 and N-methylphthalimide (22). Reaction of ketone monoxime 23 with LR resulted in the formation of the oxathiaphosphole 24 and the dithiaphosphole 25, whereas the monoxime 26 afforded the thioxoethanone thioxime 27. Ketone dioximes 28 and 34 afforded the phosphonodithioates 29 and 36, respectively, when they were allowed to react with LR, whereas the dioxime 30 gave compounds 32 and 33. Moreover, the molluscicidal potency of the newly synthesized compounds against Biomphalaria glabrata snails was studied, too.  相似文献   

10.
X-ray crystallographic studies of cobalt(III) complexes of 5-methyl-3-formylpyrazole-N(4)-diethylthiosemicarbazone (HMPzNEt2), [Co(MP z NEt 2 ) 2 ]Br·2H 2 O, 5-methyl-3-formylpyrazole-N(4)-dipropylthiosemicarbazone (HMPzNPr 2 ), [Co(MP z NPr 2 ) 2 ]Br·2H 2 O and 5-methyl-3formylpyrazole-N(4)-dibutylthiosemicarbazone (HMPzNBu 2 ), [Co(MP z NBu 2 ) 2 ]Br·H 2 O, have been reported. In all the three complex species, X-ray crystallography has authenticated a CoN4S2 octahedral coordination with the pair of orthogonally coordinated NNS tridentate ligands in the monodeprotonated form of the ligand. The two azomethine nitrogen atoms are trans to each other, while the pyrazolyl ring nitrogens and the thiolato sulfurs are in cis positions. A gradual decrease in the dihedral angle between the coordinating ligands has been observed with increase in the bulkiness of the aliphatic side chains of the substituent on the thiosemicarbazone moieties. In all the three complexes, intraligand C–H···S contacts appear to arrest the free rotation of the side chains about the C(6)–N(5) single bond. Deceased  相似文献   

11.
A series of azopyridine‐containing hydrogen bonding acceptors (4ac) with flexible spacers of oligo(methylene) were synthesised. Hydrogen‐bonded polymeric complexes 4/5 and trimeric complexes 4/62 , where 5 and 6 are aromatic dicarboxylic acids and monocarboxylic acids, respectively, were prepared and their liquid crystallinity was examined using differential scanning calorimetry and polarising optical microscopy. The study showed that most of the complexes displayed reversible thermotropic nematic phase. The isotropic to nematic phase transition temperatures of polymeric complexes 4/5 and trimeric complexes 4/62 in general decreased with the increase in length of spacers and terminal groups in the corresponding proton acceptors 4 and the proton donors 5 and 6, respectively. Hydrogen bonding interactions in complexes 4/5 and 4/62 were studied by X‐ray photoelectron spectroscopy and Fourier transform infrared spectroscopy.  相似文献   

12.
A new 9,10-dihydrophenanthrene,1,5-dihydroxy-3,4,7-trimethoxy-9,10-dihydrophenanthrene (1) was isolated and identified from the whole plants of Dendrobium moniliforme, as well as 24 known compounds including hircinol (2), (2R*,3S*)-3-hydroxymethyl-9-methoxy-2-(4′-hydroxy-3′,5′-dimethoxyphenyl)-2,3,6,7-tetrahydro-phenanthro[4,3-b]furan-5,11-diol (3), diospyrosin (4), aloifol I (5), moscatilin (6), 3,4′-dihydroxy-3′,4,5-trimethoxybibenzyl (7), gigantol (8), 3,3′-dihydroxy-4,5-dimethoxybibenzyl (9), longicornuol A (10), N-trans-cinnamoyltyramine (11), paprazine (12), N-trans-feruloyl 3′-O-methyldopamine (13), moupinamide (14), dihydroconiferyl dihydro-p-coumarate (15), dihydrosinapyl dihydro-p-coumarate (16), 3-isopropyl-5-acetoxycyclohexene-2-one-1 (17), p-hydroxybenzaldehyde (18), vanillin (19), p-hydroxyphenylpropionic acid (20), vanillic acid (21), protocatechuic acid (22), (+)-syringaresinol (23), β-sitosterol (24) and daucosterol (25). Compounds 3, 4, 13, 16, 17 and 20 were isolated from the Dendrobium genus for the first time, and compounds 2, 5, 7, 912, 14, 15, 18, 21 and 22 were originally obtained from D. moniliforme.  相似文献   

13.
Abstract

Starting material for the synthesis of Lewis A pentasaccharide (1) was azidoglucose derivative 2 which was readily transformed into the 3,4-O-unprotected derivative 3 or the 3-O-unprotected derivative 5, respectively. Reaction of 3 and O-galactosyltrichloroacetimidate 6 led preferentially to the desired β(1-3)-connected disaccharide 8 which could be selectively obtained from donor 6 and acceptor 5 via disaccharide 9. 4a-O-Fucosylation of 8 with fucosyl donor 10 furnished trisaccharide 11 which was transformed into triosyl donor 13; glycosylation of lactose derivative 14 as acceptor furnished the desired pentasaccharide in high yield. Azide reduction and N-acetylation and O-deprotection afforded the title compound 1 in high overall yield.  相似文献   

14.
Phosphono substituted-thiazolones 5a, b together with fused phosphono-pyran-5-ones 9a, b and the diolefins 8a–d were regioselectively prepared in reasonable yields from the reactions of 5-arylidene-4-thiazolidinones 1a, b with phosphonoacetates 2a, b. Conversely, Michael addition products 11a, b (~30%) along with the phosphono substituted-thiazole derivatives 12a, b (~33%) were obtained from treating 1a, b with cyanomethylenephosphonates (2c). The reactions of 1a, b with vinylphosphonate 2d proceeded with phase-transfer catalysis, yielding the corresponding 2-thioalkyl-derivatives 14a, b and phosphonates 13a, b.  相似文献   

15.
N-1-Naphthyl-3-oxobutanamide (1) reacts with arylidinecyanothioacetamide 2a–c in ethanol/piperidine solution under reflux to yield the pyridine-2(1H)-thiones 6a–c. Compound 6a reacts with α-haloketones 7a–e to give the 6-thio-N-1-naphthyl-nicotinamides derivatives 8a–e, which cyclized to thieno[2,3-b]pyridine derivatives 9ae. The reaction of compound 9a with hydrazine hydrate and formamide gives the thieno[2,3-b]pyridine carbohydrazide derivative 10 and pyridothienopyrimidine derivative 11, respectively. Reaction of 9a with benzoyl isothiocyanate gave thiourea derivative 12. Compound 12, upon treatment with alcoholic NaOH, gave pyridothienopyrimidine 13. Saponifications of 9a gave the amino acid 15, which affords 16 when refluxed in Ac2O. Treatment of compound 16 with AcONH4/AcOH gave 17. Diazotization and self-coupling of 9b gave the pyridothienotriazine 18. Also, diazotization of the ortho-aminohydrazide 10 give the corresponding azide 19, which was subjected to Curtius rearrangement in boiling xylene to give imidazothienopyridine 20. Reaction of 10 with either formic acid or triethylorthoformate and phenyl isothiocyanate gave the corresponding pyridothienotriazepines 22 and 23, respectively. The interaction of 10 with acetylacetone furnished the pyrazolyl derivative 24. The structures of the synthesized compounds were established from their analytical and spectral data.  相似文献   

16.
Mono(thio)substituted 1a–c gave compounds 3a–c and 5a with o-toluidin (2) and m-toluidin (4) in ether. Compounds 9a–c and 11a, b were obtained from the reaction of compounds 1a–c with p-fluorophenylamine (8) and p-fluorobenzylamine (10). Compounds 7a and 15c were obtained from the reaction of 1a and 1c with p-phenylendiamine (6) and o-phenylendiamine (14). Compound 13c was synthesized from the reaction of compound 1c with benzidine (2).  相似文献   

17.
Thirteen tetrahydroprotoberberines, 2,9,10-thrihydroxy-3-methoxytetrahydroprotoberberine (1), cavidine (2), thalictrifoline (3), mesotetrahydrocorysamine (4), stylopine (5), sinactine (6), apocavidine (7), cheilanthifoline (8), 13-β-hydroxystylopine (9), tetrahydropalmatine (10), tetrahydropalmatrubine (11), isocorypalmine (12), and scoulerine (13) have been isolated from the herb of Corydalis. Saxicola Bunting. Of these alkaloids, 2,9,10-thrihydroxy-3-methoxytetrahydroprotoberberine (1) was a new base. The alkaloids mesotetrahydrocorysamine (4), stylopine (5), sinactine (6), apocavidine (7), cheilanthifoline (8), 13-β-hydroxystylopine (9), tetrahydropalmatine (10), tetrahydropalmatrubine (11), isocorypalmine (12), and scoulerine (13), although previously known, were isolated for the first time from Corydalis saxicola Bunting. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 143–144, March–April, 2007.  相似文献   

18.
Abstract

Convolvulus trabutianus Schweinf. & Muschl. is an endemic plant from northern Sahara used in folk medicine. Herein we report, the isolation, characterization and evaluation of the radical scavenging properties of twenty three compounds from different extracts of this species by on-line HPLC-ABTS?+ screening. These compounds include nine phenolic acids: 2, 6, 10–16, two phytosterols: 3–4, four coumarins: 5, 7–9, two quinic acids: 21 and 22 and six flavonoids: 1, 17–20 and 23 among which the most active were: 10, 16, 21 and 22. All the extracts showed a significant antioxidant activity on-line. These results were validated off-line by ORAC and TEAC assays. Four compounds: 1, 5, 18 and 19 were described for the first time from the Convolvulaceae family, whereas compounds 2, 6, 8, 10, 13 and 21 were new for the genus Convolvulus.  相似文献   

19.
Some novel thiophenes (4a,b, 5, and 9a,b) were obtained from the cycloalkylation of the thiocarbamoyl group in the cyanothioacetanilide derivative (1) with α-halocarbonyl compounds. Also, the reaction of cyanothioacetanilide derivative with phenyl isothiocyanate in the presence of potassium hydroxide followed by in situ heterocyclization of the resulting adduct with α-halocarbonyl compounds furnished the corresponding thiazole (12, 14, and 15), pyrazole (19), and pyraozlo[1,5-a]pyrimidine (22, 25, and 26) derivatives. Compounds (4b, 5, 9a, 12, 13, 18, 22, 25, and 26) were tested to evaluate their antimicrobial activity.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.  相似文献   

20.
Abstract

The reaction of the arenethiols 4a-b with formaldehyde and the sec-amines 5a-c gave the aminomethyl aryl sulfides 6a-d. The reaction of the hemimercaptals 3a-b with 5a in methanol gave 6a-b in high yield. In acetonitrile reaction media, 6b was obtained by the reaction of 3b with 5a which suggested that 7b was not an intermediate in the formation of 6b in methanolic media. The absence of 7b in methanolic media suggests that the methylenesulfonium ion 8b is not an reaction intermediate. The formation of 7b was observed in the reaction of 3b with methanol when catalyzed by the Lewis acid tetrafluoroboric acid diethyl ether complex. The experimental observations are best explained by a mechanism whereby 3a-b are in rapid equilibrium with 4a-b under the basic reaction conditions. Rapid reaction of the liberated formaldehyde with 5a leads to the normal Mannich reaction pathway. Consistent with this mechanism, the reaction of a mixture of 3a-b and 12 with 5a gave both 6a-b and 13.  相似文献   

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