Compounds1 And2 Research Articles

Synthesis, α-Amylase Inhibitory Activity and Molecular Docking Studies of 2,4-Thiazolidinedione Derivatives

Introduction:2,4-Thiazolidinedione and its derivatives exhibit a variety of pharmacological activities including antidiabetic, antiviral, antifungal, anti-inflammatory, anti-cancer and aldose reductase inhibitory activities. Keeping in mind the pharmacological potential of 2,4-Thiazolidinedione derivatives as antidiabetic agents, seven arylidene derivatives of 2,4-thiazolidinedione1(a-g)and four corresponding acetic acid derivatives 2(a-d)have been synthesized by a three-step procedure.Methods:All the synthesized compounds were characterized by elemental analysis, FTIR,1HNMR, and13CNMR and further screened for their α-amylase inhibitory potential.Results:All the compounds1(a-g)and2(a-d)showed varying degree of α-amylase inhibition, especially compound1c(IC50= 6.59μg/ml),1d(IC50=2.03μg/ml) and1g(IC50= 3.14μg/ml) displayed significantly potent α-amylase inhibition as compared to the standard acarbose (IC50= 8.26μg/ml). None of the acetic acid derivatives of 5-arylidene-2,4-thiazolidinedione showed prominent inhibitory activity. Docking results indicated that the best binding conformation was found inside the active site cleft of enzyme responsible for hydrolysis of carbohydrates.Conclusion:Therefore, it can be concluded that 2,4-thiazolidinedione derivatives can be used as effective lead molecules for the development of α-amylase inhibitors for the management of diabetes.

Syntheses, structure and intercalation properties of low-dimensional phenylarsonates, A(HO3AsC6H5)(H2O3AsC6H5) (A = Tl, Na, K and Rb)

Four new low-dimensional phenylarsonates, A(HO3AsC6H5)(H2O3AsC6H5) (A = Tl(1), Na(2), K(3) and Rb(4)), have been synthesized and characterized by X-ray diffraction, spectroscopic and thermal studies. They crystallize in triclinic unit cells and have approximately planar arrangement of A+ ions, coordinated to oxygen atoms of phenylarsonates, on both sides. Structure of thallium phenylarsonate as determined by single crystal X-ray diffraction, is one-dimensional, whereas those of alkalimetal analogues are two-dimensional. Successful intercalation reactions of compounds1 and2 with primaryn-alkyl amines have been demonstrated.

Synthesis and structures of thienyl-substituted 5-dipyrromethane isomers

The compounds 5(2-thienyl)-and 5(3-thienyl)-dipyrromethane (1 and2, respectively) have been synthesized and isolated from the acid-catalyzed reaction between thiophenes-carboxaldehyde and pyrrole. Characterization by X-ray diffraction confirms molecular structures involving twoortho-substituted pyrrolyl and one thienyl groups. Both the compounds1 and2 were crystallized in the monoclinic space groupP21/n with cell parametersa = 5.7149(16) A,b = 17.338(6) A, andc = 11.785(4) A, β = 98.466(9)∘,V = 1155.0(6) A3 for compound1; anda = 5.828(4) A,b = 17.424(10) A,c = 11.822(8) A, β = 98.10(2)∘, andV = 1188.4(13) A3 for compound2.

ChemInform Abstract: Synthesis of Disaccharidic Sub‐Units of a New Series of Heparin Related Oligosaccharides.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Antifungal activity toPhytophthora infestans of sesquiterpenoids from infected potato tubers

The sesquiterpenes 2-(1',2'-dihydroxy-1'-methylethyl)-6,10-dimethyl-spiro-[4,5]dec-6-en-8-on (1) and its 2'-O-β-d-glucopyranoside (2) were isolated from the stress zones of potato tubers infected withPhoma foveata andFusarium spp., and rishitin and solavetivone from tuber slices inoculated withErwinia carotovora. The influence of these compounds, and of the naturally occurring plant sesquiterpenoids abscisic acid, cedrol and farnesol, on the mycelial growth ofPhytophthora infestans were tested on agar plates using a defined medium. All sesquiterpenoids suppressed the growth of the pathogen, except for1 and its glucoside2 which induced a slight, however significant, growth stimulation. Compounds1 and2 could not be isolated fromE. carotovora orP. infestans-inoculated tuber tissue.

Molecular and crystal structure of 2-cyano-(2E)-pentadien-2,4-oic acid and ethyl-2-cyano-(2E)-pentadien-2,4-oate

X-ray study of 2-cyano-(2E)-pentadien-2,4-oic acid (1) and its ethyl ester (2) showed that the molecules of1 and2 in the crystalline phase form stacks by translating along the shortest crystallographic axis. The nature of the intermolecular interactions favoring the formation of such β-structures was analyzed within the framework of the Bader topological theory. Possible routes of topochemical reactions of compounds1 and2 are considered.

Tricarbonylchromium complexes with phenalene. Synthesis, structure, and thermal rearrangements

The reaction of phenalene with Cr(CO)3Py3/BF3·OEt2 afforded a mixture of two isomeric complexes, tricarbonyl(6a,7-9,9a,9b-·6-phenalene)chromium (1) and tricarbonyl(3a,6a,9b,4-6-·6-phenalene)chromium (2). Deprotonation of the mixture of compounds1 and2 followed by treatment with MeI, BunI, or D2O gave complexesexo-1-R-1 (3–5: R=Me (3), Bun (4), or D (5)). The molecular geometry of complex3 was established by X-ray structural analysis. Heating of complex5 in toluene or C6F6 at 90–110 °C resulted in redistribution of deuterium among positionsexo-1,endo-1, and 3 in the resulting complexes of types1 and2 via sigmatropic shifts of the H exo and H endo atoms in the nonaromatic ring as well asvia inter-ring migrations of the tricarbonylchromium group. In the case of3, the methyl label is distributed among positionsexo-1 and3 to form isomeric complexes with similar structures (exo-1-Me-2 (6), 3-Me-2 (7), and 3-Me-1 (8), respectively)via processes analogous to those observed in the case of isomerization of compound5 (except for migration of the H exo atom). The mechanisms of these rearrangements are discussed.

Bis-ethanedithiolate triruthenium cluster complexes from the reaction of Ru3(CO)12 with 1,2,5, 6-tetrathiacyclooctane

The reaction of 1,2,5,6-tetrathiacyclooctane with Ru3(CO)12 in methylene chloride solvent at 40°C has yielded two new isomericbis-thane-1,2-dithiolate triruthenium carbonyl cluster complexes:anti-Ru3(CO)7(μ-SCH2CH2S)2, 1 andsyn-Ru3(CO)7(μ-SCH2CH2S)2,2, and the previously reported diruthenium compound, Ru2(CO)6(μ-SCH2CH2S).3 in 24 %, 5 %, and 26 % yields, respectively. Compounds1 and2 were characterized by a single crystal X-ray diflraction analyses. Both compounds consist of a open triangular triruthenium clusters with seven terminal carbonyl ligands and a bridging ethanedithiolate ligand across each of the metal metal bonds in the complex. When heated to 60° C, compound1 was trans[formed into a mixture of2 and3. Crystallographic data for1: Ru3S4O7C11H8, space group, P21/a,a= ll.830(2)A,b= 10.576(1)A,c= 16.012(1)A,β= 100.53(2)°,Z=4, 1808 reflections,R= 0.029. For2: Ru3 S4O7C11H8, space group P1,a= 9.945(l)A,b= 11.323(1)A.c= 9,788(1)A,a= 108.73(1)°,β= 104,67(1)°,y= 103.59(2)°,Z = 2, 2046 rellections.R = 0.021.

Studies of the oxovanadium-organophosphonate system: Formation of pyrodiphosphonate and pyrophosphophosphonate units through metal-mediated ligand condensations. The crystal and molecular structures of (Ph4P)2[VO{RP(O)2OP(O)2 R}2] (R=Me, Ph) and (Ph4P)2(n-Bu4N)[(VO)6V{t-BuP(O)2OPO3}6

Under solvothermal conditions and in the presence of oxovanadium species. organophosphonates undergo self-condensation reactions or condensation with phosphate to yield pyrodiphosphonate {RP(O)2OP(O)2R}2, or organophos-phonatophosphate units {RP(O)2OPO3}3-. In this fashion, the reactions of (Ph4P)[VO2Cl2] withRPO3H2 (R=CH3,Ph) and Et3N in CH3CN at 110°C yielded (Ph4P)2 [VO{RP(O)2P(O)2R}2](R = CH3(1), Ph (2)). However, the reaction of {Ph4P}[VO2Cl2],t-BuPO3H2 and (n-Bu4N)H2PO4 in acetonitrile at 125°C produced an unusual mixed valence V(IV)/V(III) cluster (Ph4P)2 (n-Bu4N)[(VO)6V{Me3CP(O)2OPO3}6] ⊎3CH3CN (3). Compounds1 and2 exhibit mononuclear molecular anions with the V(IV) center in the common square pyramidal coordination mode. The organodiphosphonate ligands adopt a bidentate coordination mode. The molecular anion of3 consists of a shell constructed of six V(IV) square pyramids linked by pentadentate {Me3CP(O)2OPO3}3- groups. Each organophosphonatophosphate ligand bridges four {VO5}square pyramids of the shell and directs the fifth oxygen donor toward the interior of the cluster, so as to bond to an octahedral V(III) located at the center of the cluster cavity. Crystal data:1, C26H26O5.5P3V0.5: triciinic Pl,a=10.836(2)A,b=ll.418(2)A,c=11.486(2)A,α=82.58(2)°,s=75.29(2)°,γ=75.61(2)°,V=1328.1(7)A3,Z=2, Dcalc=l.362gcm-3;2, C36H32O6.5P3V0.5: monoclinic P21/c,a=12.823(3)A,b=14.318(3)A,c=18.581(4)A,s=94.76(3)°,V=3999.7(13)A3,Z=4, Dcalc=l.342gcm-33, C94H139N4O42P14V7, triclinic Pl,a=13.589(3)A,b=17.835(4)A,c=38.915(8)A,α=81.64(2)°,s=81.58(2)°,γ=82.87(2)°,V=9180(3)A3,Z=3, Dcalc=l.512gcm-3.

Synthesis and characterization of the new mixed-metal, mixed-chalcogen clusters Fe2 M(CO)10(?3-S)(?3-Te) (M=W, Mo). crystal structure of Fe2W(CO)10(?3-S)(?3-Te)

The new clusters Fe2M(CO)10(µ3-S)(µ3-Te), I (M=W) and 2 (M=Mo) have been isolated from the room temperature reaction of Fe2(CO)6(µ-STe) andM(CO)5(THF) (M=W, Mo), respectively. Compounds1 and2 have been characterized by IR, 125 Te NMR spectroscopy, and elemental analysis. The structure of compound1 has been established by X-ray crystallography. It belongs to the triclinic space groupP\(\bar 1\) witha=6.844(2) A,b=9.397(2) A,c=13.681(10) A, α=81.64(2)°,β=81360r,γ=812(2)°,V=861.2(3) A3,Z=2,De=2.835 g cm−3. Full-matrix least-squares refinement of1 converged to R=0.043, andRw.=0.115. The structure consists of a Fe2 WSTe square pyramid and the W atom occupies the apical site of the square pyramid.

New reaction of the sodium salt of 2-nitroethanol. X-ray analysis of the sodium salt of 2-oxo-3-hydroxypropionic acid oxime, 2-bromo-2-nitropropane-1,3-diol, and the model 2,2-dinitropropane-1,3-diol

A novel reaction of the sodium salt of 2-nitroethanol in aqueous ammonia resulted in the sodium salt of 2-oxo-3-hydroxypropionic acid oxime (1) has been found. Bromination of1 affords 2-bromo-2-nitropropane-1,3-diol (2) with a previously unknown molecular conformation. The formation mechanisms of compounds1 and2 were suggested. X-ray analysis of products1,2 and that of the model compound, 2,2-dinitropropane-1,3-diol, was performed.

The synthesis and X-ray structural studies of 2-cholesteryl-2-thio-1,3,2-oxathiaphospholane and 2-cholesteryl-2-thio-1,3,2-dithiaphospholane

Two “thiophospholane” derivatives of cholesterol: 2-cholesteryl-2-thio-1,3,2-oxathiaphospholane (1) and 2-cholesteryl-2-thio-1,3,2-dithiaphospholane (2) were synthesized as new reagents for introducing a cholesteryl moiety at the 5′-end of oligonucleotidesvia the phosphorothioate or phosphorodithioate bond. Compounds1 and2 were subjected to structural studies by X-ray methods. Both compounds crystallized in the orthorhombic system, space group P212121,1 witha=6.283(1) A,b=12.067(1) A,c=38.983(3) A,2 witha=6.371(1) A,b=11.971(1) A andc=39.502(3) A. The five-membered heterocyclic rings of both compounds attain a half-chair conformation in the solid state. In structures of1 and2 a disorder of some atoms is observed. The absolute configuration at the phosphorus atom in1 of the components of diastereoisomeric mixture has been established.

Conformations of 2-C:1-N-carbonyl-2-deoxy-d-glycopyranosylamines

Geometry and molecular conformation of theN-toluenesulfonyl1 andN-acetyl-2 derivatives of peracetylated 2-C:1-N-carbonyl-2-deoxy-α-d-glucopyranosylamine were investigated with the use of X-ray diffraction methods. Compound1 (C20H23NSO10) crystallizes in the monoclinic P21 space group, withZ=2 anda=8.238(1),b=7.988(1),c=16.928(2)A, β=99.12(1)°. Compound2 (C15H19NO9) crystallizes in orthorhombic P212121 space group withZ=4 anda=8.385(1),b=8.550(1),c=24.000(2) A. Analysis of differences in bond lengths and angles between compounds1 and2 and other compounds of this class showed that the electronwithdawing effect by the residue located at the nitrogen atom can be manifested by lengthening of the β-lactam C-N bonds, with simultaneous shortening of the distance between two carbon atoms at the ring fusion. Semi-empirical calculations suggested that the title compounds displayed two positively charged centers, susceptible for attack of nucleophiles, one at the carbonyl group of β-lactam and the second at the anomeric carbon atom. Atomic charges, however, calculated for compounds1 and2 did not explain their different reaction directions during alcoholysis.

The interactions of (=O?Si)-(benzoyloxymethyl)trifluoro-and -(benzoyloxymethyl) methyldifluorosilanes with a solvent

The IR spectra of solutions of (=O→Si)-(benzoyloxymethyl)trifluorosilane (1),-(benzoyloxymethyl)methyldifluorosilane (2), and butyl benzoate (3) are examined in the region of thev(C=O) stretching vibrations in 24 solvents. The ability of compounds1—3 to undergo specific intermolecular interactions is evaluated from the dependence ofv(C=O) on the Kamlet-Taft (π*,α, β) parameters, which was obtained for the carbonyl groups involved in the intramolecular coordinate (=O→Si) bond and for free carbonyl groups. The corresponding values of the coefficients in the Kamlet-Taft equations are indicative of a weak ability of pentacoordinate silicon compounds1 and2 to undergo acid-base interactions.

Cytotoxicity of boron containing dipeptide analogs

This work is an extension of our previous work (Hall et al., 1993) on the synthesis and cytotoxic activity of boronated peptides. The aim of this work was to carry out structural modifications of the amine terminal in compounds1 and2, to increase water solubility, and its effect on the cytotoxicity to tumor cell lines. Surprisingly, only compounds4,7 and8 were more water soluble than the parent compounds. With the exception of compound4, the new derivatives were generally less effective than the parent compounds (1 and2). There was no apparent correlation between structure and activity. Cytotoxic effect was more pronounced in single cell suspended cells. The growth of solid tumor cell lines was not significantly reduced. The most active derivative, (methanamine)dihydro[[[1-(phenylmethyl)-2-methylamino-2-oxoethyl]amino]carboxy]boron (4), inhibited DNA, RNA, and protein synthesis in Tmolt3 cells. Enzymatic activities, e.g., DNA polymeraseα, m-RNA polymerase, PRPP amidotransferase, carbamyl phosphate synthetase, TMP-kinase, TDP-kinase, dihydrofolate reductase, and ribonucleoside reductase were reduced after 60 min incubation with4. d(TTP) and d(CTP) pool levels were also reduced by 60 min incubation with4.

Study of structural aspects of thermochemical conversions of compounds modeling oligophenylenes containing acenaphthylenyl and acenaphthenyl groups

With the aim of elucidating the mechanism of the thermochemical conversion of oligophenylenes containing acenaphthylenyl groups, the thermolysis of model compounds: l,3,5-tris(5-acenaphthylenyl)benzene (1), 1,3,5-tris(5-acenaphthenyl)benzene (2), acenaphthylene, and acenaphthene, was studied by differential thermal analysis (DTA), dynamic thermogravimetric analysis (TGA), and mass spectrometry. Compounds1 and2 were studied by X-ray structural analysis. A scheme for the formation of secondary structures was suggested. Optimum temperature conditions were found for preparing thermostable, heat-resistant, and stable to thermooxidation polymers based on compounds containing the acenaphthylenyl groups.

Oviposition stimulants inBarbarea vulgaris forPieris rapae andP. napi oleracea: isolation, identification and differential activity

The closely related butterflies,Pieris rapae andP. napi oleracea, readily laid eggs onBarbarea vulgaris in greenhouse cages. When offered a choice between cabbage andB. vulgaris, P. rapae showed no preference, butP. napi oleracea preferredB. vulgaris. Bioassays of extracts ofB. vulgaris foliage revealed the presence of oviposition deterrent(s) in l-butanol extracts as well as stimulants in the postbutanol water extracts. However, the deterrent effect was apparently outweighed by the strong stimulatory effect in the whole plants. The postbutanol water extract was preferred over an equivalent cabbage extract by both species, but more significantly in the case ofP. napi oleracea. The stimulants were isolated by open column chromatography and HPLC, and the activity was associated with three glucosinolates.P. napi oleracea was more sensitive thanP. rapae to the natural concentration of compounds1 and3, whereas both species were strongly stimulated to oviposit by natural concentrations of compound2. Compounds1 and2 were identified as (2R)-glucobarbarin and (2S)-glucobarbarin, respectively, and3 was identified as glucobrassicin, on the basis of their UV, mass, and NMR spectra. When the pure compounds were tested at the same concentrations applied to bean plants, the (2R)-glucobarbarin at 0.2 mg/plant was preferred over a standard cabbage extract by both butterfly species. However, at a dose of 0.02 mg/plant,P. rapae preferred the cabbage extract whereasP. napi oleracea still preferred the (2R)-glucobarbarin. No such difference in response of the two species to the same two concentrations of (2S)-glucobarbarin was obtained. The results indicate a distinct difference in sensitivity of these butterflies to the epimers of glucobarbarin, and the differences in behavioral responses of the two butterfly species depend to a large extent on the concentration of stimulant present.

Light-induced hydrogen production using waste compounds as sacrifical electron donors

Systems for the conversion and chemical storage of solar energy are usually based on photo-induced electron transfer reactions from an excited sensitizer to an electron acceptor (i.e. an electron relay compound). We have investigated the photo- and electrochemical properties of two novel electron relay compounds: l,l″,r″′-trimethyl[4,2′; 4′,4″; 6′,4″′]quaterpyridinium trichloride (1) and 1,1′,1″,1″′-tetramethyl[4,2′; 4′,4′’; 6′,4″] quaterpyridinium tetrachloride (2). When solutions containing Ru(bpy)3Cl2 or Zn-porphyrin (as photosensitizer), compound1 or2 and EDTA (as sacrificial electron donor) are irradiated by visible light (λ > 400 nm), only the formation of reduced relay compound 1 occurs. Addition of platinum catalyst to such solutions with compound 1 leads to the formation of hydrogen. Quantum yields are in the range of 5%, calculated for absorbed light. Using other sacrificial electron donors such as alcohols or glucose (or waste compounds like 4-chlorophenol) did not result in hydrogen evolution. However,1 and2 are reduced by these sacrificial electron donors in the absence of an additional photosensitizer, when near UV irradiation light (λ > 280 nm) is used. Quantum yields for hydrogen production with compound1 are about 2%, calculated for absorbed light out of GC-measurements from H2 in the gas phase above the irradiated solution. The photo- and electrochemical properties of compounds1 and2 are discussed.

1,1″,1‴-Trialkyl[4,2′;4′,4″;6′,4‴] quaterpyridinium trichlorides as electron transfer agents

Photo- and electrochemical properties of a novel class of electron transfer substances (1,1″,1‴-trialkyl[4,2′;4′,4″;6′,4‴] quaterpyridinium trichlorides) have been studied for hydrogen producing systems containing sensitizerS, electron transfer agentR, electron donorD, and platinum catalyst. 1,1″,1‴-trimethyl [4,2′;4′,4″;6′,4‴] quaterpyridinium trichloride (1) and 1,1″,1‴-tribenzyl [4,2′;4′,4″;6′,4‴] quaterpyridinium trichloride (2) quench the excited state of Ru(bipy)3Cl2. Irradiation (λ>400 nm) of solutions containing Ru(bipy)3Cl2,1 or2 and EDTA lead to the formation of radicals of1 or2. A solution of radicals of compound1 can change its colour reversibly with change of pH-values (colourless in acidic, blue in alkaline solutions). Also, compounds1 and2 are able to produce H2 without additional sensitizer (irradiation light: λ>300 nm). Hydrogen production rates, quantum yields, and turnover numbers have been determined in two different systems (S, R, D, Pt, λ>400 nm; andR, D, Pt without additional sensitizer, λ>300 nm). Hydrogen production rates with compounds1 and2 are of the same order of magnitude as those with methyl viologen. The radicals of1 and2 are much more stable against oxygen, than those of methyl viologen. Cyclovoltammetry showed that the redox potentials of compounds1 and2 are dependent on pH: increasing pH values result in more negative redox potentials. Coulometric analysis showed that e.g. compound1 could accept 5 electrons at pH=4·8 and 3·4 electrons at pH=12·6 compared to only one electron for methyl viologen (independent of pH). This behaviour is explained with reference to protonated radicals.

Clusters containing carbene ligands. 12. The synthesis and transformations of Os3(CO)11[C(Et)NMe2], the first simple carbene derivative of Os3(CO)12

The carbonylation of Os2(CO)10[μ-CH2N(Me)C(Et)](μ-H),1 at 110°C/1300 psi has yielded the carbene complex Os3(CO)11[C(Et)NMe2],2, the first simple carbene derivative of Os3(CO)12, in 68% yield. Compound2 was characterized by a single crystal structure analysis which showed the position of a dimethylaminocarbene ligand in an equatorial coordination site. Compound2 is decarbonylated at 97°C to reform1 in 59% yield. Compound1 can be decarbonylated further at 125°C to yield the new compound Os3(CO)9 [μ3-η2-C(H)N(Me)C(Et)](μ-H)2,3 in 94% yield. Compound3 was characterized by a crystal structure analysis and was shown to possess a triply bridging C(H)N(Me)C(Et) ligand containing two carbene centers. Compounds1 and2 can be regenerated from3 by carbonylation with CO at 110°C/800 psi. The facile activation of the N-methyl CH bonds of the carbene ligand of2 is produced by the metal atoms adjacent to the carbene coordination site, and may be a characteristic feature of the chemistry of carbene ligands in clusters. For2: space group=P $$\bar 1$$ ,a=11.407(2) A,b=12.332(2) A,c=8.602(1) A, α=103.92(1), β=110.56(1)°, γ=82.57(1),Z=2, 2627 reflections,R=0.031; for3: space group=C2/c,a=17.160(3) A,b=8.947(2) A,c=27.034(6) A, β=97.82(1)°,Z=8, 2044 reflections,R=0.038.