Metal complexes of 2-(o-hydroxyphenyl)pyridine

Complexes of 2-(o-hydroxyphenyl)pyridine (PhOHpy) with group VIIIB metal ions were synthesized and characterized by elemental analysis and spectroscopic measurements. The crystal and molecular structures of Co(PhOpy)₃ and Pd(PhOpy)₂ were determined. The Co complex crystallizes in the orthorhombic space group Fdd2, with a = 28.185- (14), b = 36.639(18), c = 12.639(18) Å; Z = 16. The molecule has a mer-octahedral structure. Crystals of the Pd complex are orthorhombic, space group Pbca, with a = 17.140(3), b = 11.143(2), c = 9.488(2) Å, Z = 4. The molecule is square-planar.     

An experimental and theoretical approach to the molecular structure of 2-{4-[3-(2,5-dimethylphenyl)-3-methylcyclobutyl]thiazol-2-yl}isoindoline-1,3-dione

The title compound, 2-{4-[3-(2,5-dimethylphenyl)-3-methylcyclobutyl]thiazol-2-yl}isoindoline-1,3-dione (C₂₄H₂₂N₂O₂S), was synthesized and characterized by IR-NMR spectroscopy and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P2₁/c with a?=?19.7799(13) Å, b?=?6.7473(4) Å, c?=?15.7259(9) Å and β?=?103.416(5)°. In addition, the molecular geometry, vibrational frequencies and gauge including atomic orbital (GIAO) ¹H and ¹³C chemical shift values of the title compound in the ground state have been calculated by using the Hartree-Fock (HF) and density functional method (DFT/B3LYP) with 6–31G(d), 6–31 + G(d,p) and LANL2DZ basis sets, and compared with the experimental data. To determine conformational flexibility, molecular energy profile of the title compound was obtained by semi-empirical (AM1) calculations with respect to two selected degrees of torsional freedom, which were varied from ?180° to +180° in steps of 5°. Besides, molecular electrostatic potential, frontier molecular orbitals (FMO) analysis and thermodynamic properties of the title compound were investigated by theoretical calculations.     

Experimental and theoretical investigation of the molecular and electronic structure of 5-(4-aminophenyl)-4-(3-methyl-3-phenylcyclobutyl)thiazol-2-amine

The title molecule, 5-(4-aminophenyl)-4-(3-methyl-3-phenylcyclobutyl)thiazol-2-amine (C₂₀H₂₁N₃S), was prepared and characterized by ¹H-NMR, ¹³C-NMR, IR and single-crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P2₁/c with a?=?9.4350(5) Å, b?=?11.2796(6) Å, c?=?18.4170(8) Å and β?=?113.378(3)°. In addition to the molecular geometry from X-ray experiment, the molecular geometry, vibrational frequencies, gauge including atomic orbital (GIAO) ¹H- and ¹³C-NMR chemical shift values and atomic charges distribution of the title compound in the ground state have been calculated using the Hartree–Fock (HF) and density functional method (DFT) (B3LYP) with 6-31G(d) basis set. To determine conformational flexibility, molecular energy profile of the title compound was obtained by semi-empirical (AM1) calculations with respect to two selected degrees of torsional freedom, which were varied from ?180° to +180° in steps of 10°. Besides, frontier molecular orbitals (FMO) analysis was performed by the B3LYP/6-31G(d) method.     

Crystal and molecular structures of substituted α-d-glucopyranosides

The crystal and molecular structures of methyl 2,4,6-tri-O-pivaloyl-α-d-glucopyranoside (1), methyl 4,6-O-(R)-benzylidene-2-O-pivaloyl-α-d-glucopyranoside (2), and methyl 4,6-O-(R)-benzylidene-2,3-di-O-pivaloyl-α-d-glucopyranoside (3) were determined by X-ray analysis. Crystals of 1 are orthorhombic, space group P2₁2₁2₁ with the unit cell a = 13.026(2), b = 16.832, c = 11.929(2) Å, Z = 4. Crystals of 2 are monoclinic, space group P2₁. The unit-cell parameters are a = 6.519(1), b = 14.664(4), c = 10.635(4) Å, β = 93.18(1)°, Z = 2. Crystals of 3 are orthorhombic, space group P2₁2₁2₁ with a = 10.006(3), b = 13.874(3), c = 18.527(5) Å, Z = 4. The structures were solved by MULTAN and refined by a full-matrix procedure to final values of R = 0.084 (1), 0.048 (2), and 0.069 (3). The pyranose ring in each compound adopts the ⁴C₁ conformation. The 1,3-dioxane rings in 2 and 3 show a chair conformation. The molecular packing in 1 is through the hydrogen bonds involving HO-3 and the 6-O-pivaloyl carbonyl group [HO-3 ⋯ O-9, 2.855(8) Å], which connect the molecules into a chain along

. The endocyclic oxygen atom is involved in an intermolecular hydrogen-bond with HO-3 [2.848(4) Å], joining molecules of 2 into the chains along

. There are no free hydroxyl groups in 3 and molecular packing reflects van der Waals interactions only.     

Engineering of glucoside acceptors for the regioselective synthesis of beta-(1-->3)-disaccharides with glycosynthases

Glycosynthase mutants obtained from Thermotogamaritima were able to catalyze the regioselective synthesis of aryl β-d-Galp-(1→3)-β-d-Glcp and aryl β-d-Glcp-(1→3)-β-d-Glcp in high yields (up to 90 %) using aryl β-d-glucosides as acceptors. The need for an aglyconic aryl group was rationalized by molecular modeling calculations, which have emphasized a high stabilizing interaction of this group by stacking with W312 of the enzyme. Unfortunately, the deprotection of the aromatic group of the disaccharides was not possible without partial hydrolysis of the glycosidic bond. The replacement of aryl groups by benzyl ones could offer the opportunity to deprotect the anomeric position under very mild conditions. Assuming that benzyl acceptors could preserve the stabilizing stacking, benzyl β-d-glucoside firstly assayed as acceptor resulted in both poor yields and poor regioselectivity. Thus, we decided to undertake molecular modeling calculations in order to design which suitable substituted benzyl acceptors could be used. This study resulted in the choice of 2-biphenylmethyl β-d-glucopyranoside. This choice was validated experimentally, since the corresponding β-(1→3) disaccharide was obtained in good yields and with a high regioselectivity. At the same time, we have shown that phenyl 1-thio-β-d-glucopyranoside was also an excellent substrate leading to similar results as those obtained with the O-phenyl analogue. The NBS deprotection of the S-phenyl group afforded the corresponding disaccharide quantitatively.     

Polyhydroxylated azetidine iminosugars: Synthesis,glycosidase inhibitory activity and molecular docking studies

An efficient and practical strategy for the synthesis of unknown azetidine iminosugars (2S,3R,4S)-2-((R)-1,2-dihydroxyethyl)-3-hydroxy-4-(hydroxymethyl)azetidine 2, (2S,3r,4R)-3-hydroxy-2,4-bis(hydroxymethyl)azetidine 3 and (2S,3R,4S)-3-hydroxy-4-(hydroxymethyl)-N-methylazetidine-2-carboxylic acid 4, starting from the d-glucose has been reported. The methodology involves preparation of the 3-amino-N-benzyloxycarbonyl-3-deoxy-6-O-tert-butyldimethylsillyl-1,2-O-isopropylidene-α-d-glucofuranose 9, which was converted to the C-5-OMs derivative 11. Intramolecular nucleophilic displacement of the C-5-OMs group with in situ generated 3-amino functionality provided the required key azetidine ring skeletons 10 with additional hydroxymethyl group. Removal of 1,2-acetonide protection, followed by reduction and hydrogenolysis afforded azetidine iminosugar 2. Alternatively, removal of 1,2-acetonide group and chopping of C1-anomeric carbon gave C2-aldehyde that on reduction or oxidation followed by hydrogenolysis gave 2,4-bis(hydroxymethyl) azetidine iminosugars 3 and N-methylazetidine-2-carboxylic acid 4 respectively. The glycosidase inhibitory activity of 2–4 iminosugars was screened against various glycosidase enzymes and compared with a standard miglitol. Amongst synthesized targets, the compound 2 was found to be more potent amyloglucosidase inhibitor than miglitol. These results were supported by molecular docking studies.     

Brevibacillus laterosporus strain BPM3, a potential biocontrol agent isolated from a natural hot water spring of Assam, India

A bacterial strain designated as BPM3 isolated from mud of a natural hot water spring of Nambar Wild Life Sanctuary, Assam, India, strongly inhibited growth of phytopathogenic fungi (Fusarium oxysporum f. sp. ciceri, F. semitectum, Magnaporthe grisea and Rhizoctonia oryzae) and gram-positive bacterium (Staphylococcus aureus). The maximum growth and antagonistic activity was recorded at 30 °C, pH 8.5 when starch and peptone were amended as carbon and nitrogen sources, respectively. In greenhouse experiment, this bacterium (BPM3) suppressed blast disease of rice by 30-67% and protected the weight loss by 35-56.5%. The maximum disease protection (67%) and weight loss protection (56.5%) were recorded when the bacterium was applied before 2 days of the pathogen inoculation. Antifungal and antibacterial compounds were isolated from the bacterium which also inhibited the growth of these targeted pathogens. The compounds were purified and on spectroscopic analysis of a purified fraction having R_f 0.22 which showed strong antifungal and antibacterial activity indicated the presence of C-H, carbonyl group, dimethyl group, -CH₂ and methyl group. The bacterium was characterized by morphological, biochemical and molecular approaches and confirmed that the strain BPM3 is Brevibacillus laterosporus.     

Differentially expressed genes: OCT-4, SOX2, STAT3, CDH1 and CDH2, in cultured mesenchymal stem cells challenged with serum of women with endometriosis

Endometriosis is a common chronic gynecological disorder defined as the presence of ectopic functional endometrial tissues, outside uterine cavity, primarily on the pelvic peritoneum and the ovaries. Several studies revealed a correlation between aberrant stem-cell activity in the endometrium and endometriosis. Yet the molecular and cellular behaviors of mesnchymal stem cells in development of endometriosis are hampered by lack of invitro experiments. Our aim was to explore morphological and molecular changes associated with mesenchymal stem cells (MSCs) exposition to serum derived from women with severe endometriosis. Two cell cultures of MSCs isolated from endometrial tissues of two endometriosis-free women. Each cell culture was treated individually with the serum of women with endometriosis (experimental group/n =?7), and serum of women without endometriosis (control group/ n = 4) for 14?days. Quantitative Real-Time PCR was performed later to reveal expression of OCT-4, CDH1 and CDH2, STAT3 and SOX2 genes. Morphologically, cells showed no significant changes. However from molecular point of view, we found increased expression in OCT-4, CDH1 and CDH2. For STAT3 and SOX2 we did not find a significant difference. This study shows that endometriosis serum induced molecular changes in human endometrial MSCs (EnMSCs) that might be related to altered cell behavior which may be a step in differentiation that may be completed invivo by other factors to complete the process of transition. Further researches are needed for optimization to reach differentiation.     

Differential stress response in rats subjected to chronic mild stress is accompanied by changes in CRH-family gene expression at the pituitary level

The purpose of this study was to examine molecular markers of the stress response at the pituitary and peripheral levels in animals that responded differently to chronic mild stress (CMS). Rats were subjected to 2-weeks CMS and symptoms of anhedonia was measured by the consumption of 1% sucrose solution. mRNA levels of CRH-family neuropeptides (Crh—corticotropin-releasing hormone, Ucn1—urocortin 1, Ucn2—urocortin 2, Ucn3—urocortin 3), CRH receptors (Crhr1—corticotropin-releasing hormone receptor 1, Crhr2—corticotropin-releasing hormone receptor 2) and Crhbp (corticotropin-releasing factor binding protein) in the pituitaries of rats were determined with real-time PCR. Plasma levels of ACTH (adrenocorticotropin), CRH and urocortins were measured with ELISA assays. CMS procedure led to the development of anhedonia manifested by the decreased sucrose consumption (stress-reactive, SR, stress-susceptible group). Additionally, the group of animals not exhibiting any signs of anhedonia (stress non-reactive, SNR, stress-resilient group) and the group characterized by the increased sucrose consumption (stress invert-reactive group SIR) were selected. The significant increases in ACTH plasma level accompanied by the decreases in the pituitary gene expression of the Crh, Ucn2 and Ucn3 in both stress non-reactive and stress invert-reactive groups were observed. The only molecular change observed in stress-reactive group was the increase in UCN2 plasma level. The differentiated behavioral stress responses were reflected by gene expression changes in the pituitary. Alterations in the mRNA levels of Crh, Ucn2 and Ucn3 in the pituitary might confirm the paracrine and/or autocrine effects of these peptides in stress response. The opposite behavioral effect between SNR vs. SIR groups and the surprising similarity at gene expression and plasma ACTH levels in these two groups may suggest the discrepancy between molecular and behavioral stress responses; however, there results might indicate to similarity underlying different ways to cope with stress conditions.     

Mechanism and stereospecificity of alpha-hydroxylation of lignoceric acid in rat brain.

Cerebronic acid (2-hydroxytetracosanoic acid) is the major fatty acid component of cerebrosides and sulfatides in mammalian brain. Our previous communication demonstrated the synthesis of cerebronic acid from lignoceric acid (tetracosanoic acid) by a rat brain preparation in the presence of molecular oxygen and a reduced pyridine nucleotide (Hoshi, M., and Kishimoto, Y. (1973) J. Biol. Chem., 248, 4123–4130). The present'studies on the conversion of (RS)-[2-³H]-, (RS)-[3-³H]-, (R)-[2-³H]-, and (S)-[2-³H]lignoceric acids to cerebronic acid by rat brain preparations establish that the pro-R hydrogen at the α-carbon of lignoceric acid is replaced by a hydroxyl group with overall retention of configuration.     

Susceptibility of plasmenyl glycerophosphoethanolamine lipids containing arachidonate to oxidative degradation

Plasmenyl phospholipids (1-alk-1′-enyl-2-acyl-3-glycerophospholipids, plasmalogens) are a structurally unique class of lipids that contain an α-unsaturated ether substituent at the sn-1 position of the glycerol backbone. Several studies have supported the hypothesis that plasmalogens may be antioxidant molecules that protect cells from oxidative stress. Because the molecular mechanisms responsible for the antioxidant properties of plasmenyl phospholipids are not fully understood, the oxidation of plasmalogens in natural mixtures of phospholipids was studied using electrospray tandem mass spectrometry. Glycerophosphoethanolamine (GPE) lipids from bovine brain were found to contain six major molecular species (16:0p/18:1-, 18:1p/18:1-, 18:0p/20:4-, 16:0p/20:4, 18:0a/20:4-, and 18:0a/22:6-GPE). Oxidation of GPE yielded lyso phospholipid products derived from plasmalogen species containing only monounsaturated sn-2 substituents and diacyl-GPE with oxidized polyunsaturated fatty acyl substituents at sn-2. The only plasmalogen species remaining intact following oxidation contained monounsaturated fatty acyl groups esterified at sn-2. The mechanism responsible for the rapid and specific destruction of plasmalogen GPE may likely involve unique reactivity imparted by a polyunsaturated fatty acyl group esterified at sn-2. This structural feature may play a central role determining the antioxidant properties ascribed to this class of phospholipids.     

Immunoreactivity and neutralization study of Chinese Bungarus multicinctus antivenin and lab-prepared anti-bungarotoxin antisera towards purified bungarotoxins and snake venoms

Bungarus multicinctus is the most venomous snake distributed in China and neighboring countries of Myanmar, Laos, north Vietnam and Thailand. The high mortality rate of B. multicinctus envenomation is attributed to the lethal components of α-, β-, γ- and κ- bungarotoxins contained in the venom. Although anti-B. multicinctus sera were produced in Shanghai, Taiwan and Vietnam, the most widely clinic used product was term as B. multicinctus antivenin and manufactured by Shanghai Serum Bio-technology Co. Ltd. In the present investigation, high purity α-, β- and γ-bungarotoxins were separately isolated from B. multicinctus crude venom. Rabbit anti- α-, β- and γ-bungarotoxin antisera were prepared by common methods, respectively. LD₅₀ values of α-, β- and γ-bungarotoxins were systematically determined via three administration pathways (intraperitoneal, intramuscular and intravenous injections) in Kunming mice. LD₅₀ values of β-bungarotoxin were closely related with injection routines but those of both α- and γ-bungarotoxins were not dependent on the injection routines. Commercial B. multicinctus antivenin showed strong immunoreaction with high molecular weight fractions of the B. multicinctus but weakly recognized low molecular weight fractions like α- and γ-bungarotoxins. Although B. multicinctus antivenin showed immunoreaction with high molecular weight fractions of Bungarus fasciatus, Naja atra, Ophiophagus hannah venoms but the antivenin only demonstrated animal protection efficacy against O. hannah venom. These results indicated that the high molecular weight fractions of the O. hannah played an important role in venom lethality but those of B. fasciatus and N. atra did not have such a role.     

Molecular characterization of a wheat–Psathyrostachys huashanica Keng 2Ns disomic addition line with resistance to stripe rust

We characterized a wheat–Psathyrostachys huashanica derived line 3-6-4-1 based on genomic in situ hybridization (GISH), molecular marker analysis, and agronomic trait evaluations. The GISH investigations showed that the 3-6-4-1 contained 42 wheat chromosomes and a pair of P. huashanica chromosomes. The homoeologous relationships of the introduced P. huashanica chromosomes were determined using EST-STS multiple loci markers from seven wheat homoeologous groups in the parents and the addition line. Twelve EST-STS markers located on the homoeologous group 2 chromosomes of wheat amplified polymorphic bands in 3-6-4-1, which were unique to P. huashanica. An introduced Ns chromosome pair that belonged to homoeologous group 2 was identified using chromosome-specific markers. Inoculation with isolates of the stripe rust pathotypes, CYR31, CYR32, and SY11-14, and mixed races (CYR31, CYR32, and SY11-14) in the seeding and adult stage, respectively, showed that 3-6-4-1 was generally resistant to stripe rust, which was probably attributable to its P. huashanica parent. We also compared a complete set of wheat–P. huashanica disomic addition lines (1Ns–7Ns, 2n = 44 = 22II) to assess their agronomic traits and morphological characteristics, which showed that 3-6-4-1 had improved spike traits compared with its parents. The P. huashanica 2Ns chromosome-specific molecular markers in 3-6-4-1 could be useful for marker-assisted selection in breeding programs to combat stripe rust. This line can be used as a donor source to introduce novel excellent genes from P. huashanica into wheat to widen its genetic diversity, thereby providing new germplasms for wheat breeding.     

Identification of cis-9,10-methylenehexadecanoic acid in submitochondrial particles of bovine heart

Submitochondrial particles of bovine heart were hydrolyzed by phospholipase A₂ and the products were analyzed by liquid chromatography electrospray ionization-mass spectrometry. We found a fatty acid with a molecular mass of 268 Da and a retention time longer than that of linoleic acid. Next, we synthesized organically cis-9,10-methylenehexadecanoic acid, which has a molecular mass similar to that of the extracted fatty acid, and characterized its high performance liquid chromatography and gas chromatography-mass spectrometry profiles. Using these data we were able to identify endogenous cis-9,10-methylenehexadecanoic acid in rat and human heart and liver tissues that had been hydrolyzed by phospholipase A₂. This fatty acid was not detected in tissue extracts that had not been hydrolyzed by phospholipase A₂. Similar amounts of cis-9,10-methylenehexadecanoic acid were measured in tissue extracts after total hydrolysis. These results suggest that cis-9,10-methylenehexadecanoic acid is a fatty acid component, in the sn-2 position, of phospholipids in some mammalian tissue.     

Cybebe gracilenta in an ITS/5.8S rDNA based phylogeny belongs to Chaenotheca (Coniocybaceae,lichenized Ascomycetes)

Abstract:Cybebe was described as a monotypic genus in the Coniocybaceae distinguished from Chaenotheca by its unusual ascus ontogeny and its unpigmented spore wall. In a molecular phylogeny based on maximum parsimony analyses of their ITS1-5.8S-ITS2 rDNA sequences, specimens of Cybebe gracilenta formed a strongly supported group with Chaenotheca gracillima. This group in turn is also well supported as a part ofChaenotheca indicating that the features characteristic of Cybebe are indeed autapomorphic and that Cybebe gracilenta should be included in Chaenotheca.     

Synthesis and structure–activity relationship of 2-phenyliminochromene derivatives as inhibitors for aldo–keto reductase (AKR) 1B10

Inhibitors of a human member (AKR1B10) of the aldo–keto reductase superfamily are regarded as promising therapeutics for the treatment of cancer. Recently, we have discovered (Z)-2-(4-methoxyphenylimino)-7-hydroxy-N-(pyridin-2-yl)-2H-chromene-3-carboxamide (1) as the potent competitive inhibitor using the virtual screening approach, and proposed its 4-methoxy group on the 2-phenylimino moiety as an essential structural prerequisite for the inhibition. In this study, 18 derivatives of 1 were synthesized and their inhibitory potency against AKR1B10 evaluated. Among them, 7-hydroxy-2-(4-methoxyphenylimino)-2H-chromene-3-carboxylic acid benzylamide (5n) was the most potent inhibitor showing a K_i value of 1.3 nM. The structure–activity relationship of the derivatives indicated that the 7-hydroxyl group on the chromene ring, but not the 4-methoxy group, was absolutely required for inhibitory activity, The molecular docking of 5n in AKR1B10 and site-directed mutagenesis of the enzyme residues suggested that the hydrogen-bond interactions between the 7-hydroxyl group of 5n and the catalytic residues (Tyr49 and His111) of the enzyme, together with a π-stacking interaction of the benzylamide moiety of 5n with Trp220, are important for the potent inhibition.     

An accurate and versatile method for determining the acyl group-introducing position of lysophospholipid acyltransferases

Lysophospholipid acyltransferases (LPLATs) incorporate a fatty acid into the hydroxyl group of lysophospholipids (LPLs) and are critical for determining the fatty acid composition of phospholipids. Previous studies have focused mainly on their molecular identification and their substrate specificity regarding the polar head groups and acyl-CoAs. However, little is known about the positional specificity of the hydroxyl group of the glycerol backbone (sn-2 or sn-1) at which LPLATs introduce a fatty acid. This is mainly due to the instability of LPLs used as an acceptor, especially for LPLs with a fatty acid at the sn-2 position of the glycerol backbone (sn-2-LPLs), which are essential for the enzymatic assay to determine the positional specificity. In this study, we established a method to determine the positional specificity of LPLAT by preparing stable sn-2-LPLs in combination with PLA₂ digestion, and applied the method for determining the positional specificity of several LPLATs including LPCAT1, LYCAT and LPCAT3. We found that LPCAT1 introduced palmitic acid both at the sn-1 and sn-2 positions of palmitoyl-LPC, while LYCAT and LPCAT3 specifically introduced stearic acid at the sn-1 position of LPG and arachidonic acid at the sn-2 position of LPC, respectively. The present method for evaluating the positional specificity could also be used for biochemical characterization of other LPLATs.     

Molecular cytogenetic identification of a wheat–Psathyrostachys huashanica Keng 5Ns disomic addition line with stripe rust resistance

We developed a new stripe rust resistant line of common wheat–Psathyrostachys huashanica Keng (2n = 2x = 14, NsNs) from a cross between wheat cv. 7182 and P. huashanica via embryo culture, and we refer to this line as 3-8-10-2. We characterized this new line by cytology, genomic in situ hybridization (GISH), EST-SSR, EST-STS, and disease resistance screening. GISH using P. huashanica genomic DNA as the probe indicated that a pair of Ns chromosomes with strong hybridization signals was introduced into 3-8-10-2. We screened 255 EST-SSR and EST-STS multiple-loci markers from seven wheat homoeologous groups in the parent lines. Of these, 90 markers were polymorphic with a polymorphism frequency of 40 %, while two EST-SSR markers and six EST-STS markers located on wheat chromosome group 5 produced specific bands in P. huashanica and 3-8-10-2, respectively. This suggested that the introduced Ns chromosome pair belonged to homoeologous group 5, which was identified using new genome-specific markers. After inoculation with stripe rust isolates, 3-8-10-2 exhibited stripe rust resistance that probably originated from its P. huashanica parent. 3-8-10-2 can be used as a donor source for introducing novel disease resistance genes into wheat during breeding programs with the assistance of molecular and cytogenetic markers. Moreover, 3-8-10-2 had improved agronomic characteristics compared with its parents. Therefore, the addition line could be exploited as an important bridge for wheat breeding and chromosome engineering.     

Methyl 2-methoxy-7-(4-methylbenzoyl)-4-oxo-6-p-tolyl-4H-furo[3,2-c]pyran-3-carboxylate:A combined experimental and theoretical investigation

The title compound, methyl 2-methoxy-7-(4-methylbenzoyl)-4-oxo-6-p-tolyl-4H-furo[3,2-c]pyran-3-carboxylate (C₂₅H₂₀O₇), was prepared and characterized by IR and single-crystal X-ray diffraction (XRD). The compound crystallizes in the triclinic space group P ?1 with a?=?8.9554(9) Å, b?=?10.0018(10) Å, c?=?12.7454(13) Å, α?=?67.678(7)°, β?=?89.359(8)° and γ?=?88.961(8)°. In addition to the molecular geometry from X-ray experiment, the molecular geometry and vibrational frequencies of the title compound in the ground state have been calculated using semiempirical AM1 and PM3 methods, as well as Hartree-Fock (HF) and density functional (B3LYP) levels of theory with 6–31G(d) basis set. To determine conformational flexibility, molecular energy profile of the title compound was obtained by semi-empirical (AM1) calculations with respect to two selected degrees of torsional freedom, which were varied from ?180° to +180° in steps of 10°. Besides, frontier molecular orbitals (FMO) analysis and thermodynamic properties of the title compound were performed by the B3LYP/6–31G(d) method.     

Glycinin composition of several perennial species related to soybean

The 7S and 11S seed storage proteins from four perennials related to soybean (Glycine canescens, G. tomentella, G. tabacina, and G. clandestina) were analyzed by sodium dodecyl sulfate-gel electrophoresis. Each species yielded a unique electrophoretic pattern that varied in the total number of bands and their relative mobilities. In every case, the electrophoretic patterns were substantially different from CX635-1-1-1, the strain of G. max used in this study for comparison. Size heterogeneities among both the 7S and 11S polypeptides of the perennials were evident.

Abundant proteins in the 11S fraction from G. tomentella (CSIRO No. 1133) were separated by chromatography on DEAE-Sephadex and then their apparent molecular weights, amino acid compositions, and NH₂-terminal amino acid sequences were determined. A group of proteins were obtained which resembled the A_1b-polypeptide components of glycinin from G. max. They had the same size (M_r 37,000), identical NH₂-terminal sequences, and similar amino acid compositions to A_1b. A second group of acidic proteins (M_r 50,000) in G. tomentella had NH₂-terminal sequences homologous to the A₅ component (M_r 10,000) of glycinin. The latter group of polypeptides had a substantially higher apparent molecular weight than any acidic polypeptide components of glycinin analyzed previously. A third group of polypeptides purified from G. tomentella were the same size as basic polypeptides of glycinin and had homologus NH₂-terminal sequences. The results indicated that the perennials exhibit variability in their seed proteins at a level not found among the cultivars of G. max and G. soja and may be useful in studies concerning the origin and organization of genes involved in the synthesis of storage proteins in cultivated soybeans.