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Herein, an accurate and sensitive method was developed for detecting four stereoisomers of propiconazole in "Fengtang" plum by LC-MS/MS. The mean recovery of four propiconazole stereoisomers ranged from 79.42 to 104.10% at three adding levels with reasonable RSD of 1.54–11.68%, and the LOD and LOQ of the four stereoisomers was 0.0005 mg/kg and 0.004 mg/kg, respectively. In addition, the residue and selective degradation of propiconazole stereoisomers in plums were investigated by storage at 20 °C and 4 °C. The half-lives of propiconazole stereoisomeric during storage were 9.49–15.40 d at 20 °C, and 21.00–28.88 d at 4 °C. The degradation of (2R,4R)-propiconazole and (2R,4S)-propiconazole in stored plums was slightly slower than that of the corresponding enantiomers (2S,4S)-propiconazole and (2S,4R)-propiconazole. The total residues of propiconazole were 0.026–0.487 mg/kg in the plum storage period, and the water washing could remove 49.35% to 54.65% of the propiconazole residue in plum. The hardness of plums treated with propiconazole was generally higher than that of control in the middle and late stages of storage. The effects of propiconazole on the total soluble solid content of plums were different at 20 °C and 4 °C. This study provides a scientific reference for the food safety evaluation of the "Fengtang" plum after the application of propiconazole during the storage period. [ABSTRACT FROM AUTHOR]

Isoxazoline structures are widely found in natural products and are rich in biological activities. This study discloses the development of a series of novel isoxazoline derivatives by introducing acylthiourea fragments to access insecticidal activity. All synthetic compounds were examined for their insecticidal activity against Plutella xylostella, with results showing moderate to strong activity. Based on this, the structure–activity relationship analysis was carried out via the constructed three-dimensional quantitative structure–activity relationship model to further guide the structure optimization, resulting in the optimal compound 32. The LC50 of compound 32 against Plutella xylostella was 0.26 mg/L, demonstrating better activity than the positive control, ethiprole (LC50 = 3.81 mg/L), avermectin (LC50 = 12.32 mg/L), and compounds 1–31. The insect GABA enzyme-linked immunosorbent assay demonstrated that compound 32 might act on the insect GABA receptor, and the molecular docking assay further illustrated the mode of action of compound 32 with the GABA receptor. In addition, the proteomics analysis indicated that the action of compound 32 on Plutella xylostella was multi-pathway. [ABSTRACT FROM AUTHOR]

Neuro-glia antigen 2/chondroitin sulfate proteoglycan 4 (NG2/CSPG4, also called MCSP, HMW-MAA, MSK16, MCSPG, MEL-CSPG, or gp240) is a large cell-surface antigen and an unusual cell membrane integral glycoprotein frequently expressed on undifferentiated precursor cells in multiple solid organ cancers, including cancers of the liver, pancreas, lungs, and kidneys. It is a valuable molecule involved in cancer cell adhesion, invasion, spreading, angiogenesis, complement inhibition, and signaling. Although the biological significance underlying NG2/CSPG4 proteoglycan involvement in cancer progression needs to be better defined, based on the current evidence, NG2/CSPG4+ cells, such as pericytes (PCs, NG2+/CD146+/PDGFR-β+) and cancer stem cells (CSCs), are closely associated with the liver malignancy, hepatocellular carcinoma (HCC), pancreatic malignancy, and pancreatic ductal adenocarcinoma (PDAC) as well as poor prognoses. Importantly, with a unique method, we successfully purified NG2/CSPG4-expressing cells from human HCC and PDAC vasculature tissue blocks (by core needle biopsy). The cells appeared to be spheres that stably expanded in cultures. As such, these cells have the potential to be used as sources of target antigens. Herein, we provide new information on the possibilities of frequently selecting NG2/CSPG4 as a solid organ cancer biomarker or exploiting expressing cells such as CSCs, or the PG/chondroitin sulfate chain of NG2/CSPG4 on the cell membrane as specific antigens for the development of antibody- and vaccine-based immunotherapeutic approaches to treat these cancers. [ABSTRACT FROM AUTHOR]

Dimethacarb is a carbamate insecticide developed in China that contains 3,5-dimethylphenyl methylcarbamate (XMC) and 3,4-dimethylphenyl methylcarbamate (MPMC) isomers. Dimethacarb has been registered for use in rice in China, but no residue or degradation of dimethacarb in rice has been reported and the maximum residue limits (MRLs) for rice have not been established. A versatile high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed with modified QuEChERS sample preparation to determine two isomers of dimethacarb in rice. The average recovery of XMC and MPMC in brown rice, rice husk, and rice straw ranged from 71.69 to 100.60%, with spike levels of 0.01 to 1 mg/kg and relative standard deviations (RSDs) of 0.21 to 8.41%. Field experiments showed that the half-lives of XMC and MPMC in rice straw were 4.08 to 4.23 days and 3.48 to 3.69 days, respectively. Final residues of XMC and MPMC in rice husk after 21 days of spraying at six sites ranged from 0.23–2.65 mg/kg and 0.06–1.10 mg/kg, and <0.01–0.16 mg/kg and <0.01–0.04 mg/kg in brown rice. The ratio of XMC to MPMC content in the rice husk differed from the original 50% dimethacarb EC, indicating the difference in the degradation rate of XMC and MPMC. The estimated risk quotient (RQ) for both XMC and MPMC was less than 30%. These data for residues from six representative locations could provide a reference for establishing the MRL of dimethacarb in rice. [ABSTRACT FROM AUTHOR]

Molecular targets play important roles in agrochemical discovery. Numerous pesticides target the key proteins in pathogens, insect, or plants. Investigating ligand-binding pockets and/or active sites in the proteins' structures is usually the first step in designing new green pesticides. Thus, molecular target structures are extremely important for the discovery and development of such pesticides. In this manuscript, we present a review of the molecular target structures, including those of antiviral, fungicidal, bactericidal, insecticidal, herbicidal, and plant growth-regulator targets, currently used in agrochemical research. The data will be helpful in pesticide design and the discovery of new green pesticides. [ABSTRACT FROM AUTHOR]

Rice bacterial leaf blight and leaf streak are two important bacterial diseases of rice, which can result in yield loss. Currently, effective antimicrobials for rice bacterial diseases are still lacking. Thus, to develop highly effective and low-risk bactericides, 31 novel 1,3,4-oxadiazole derivatives containing a cinnamic acid moiety were designed and synthesized. Bioassay results demonstrated that all compounds exhibited good antibacterial activities in vitro. Significantly, compounds 5r and 5t showed excellent antibacterial activities against Xanthomonas oryzae pv. oryzae (Xoo) and X. oryzae pv. oryzicola (Xoc), with the 50% effective concentration (EC50) values of 0.58 and 0.34, and 0.44 and 0.20 μg/mL, respectively. These compounds were much better than thiodiazole copper (123.10 and 161.52 μg/mL) and bismerthiazol (85.66 and 110.96 μg/mL). Moreover, compound 5t had better protective and curative activities against rice bacterial leaf blight and leaf streak than thiodiazole copper and bismerthiazol in vivo. Simultaneously, the in vivo efficacy of the compounds was demonstrated by real-time quantitative PCR to quantify bacterial titers. In addition, a three-dimensional quantitative structure–activity relationship model was created and presented good predictive ability. This work provides support for 1,3,4-oxadiazole derivatives containing a cinnamic acid moiety as a potential new bactericide for rice bacterial diseases. [ABSTRACT FROM AUTHOR]

Plant immune activators can protect crops from plant virus pathogens by activating intrinsic immune mechanisms in plants and are widely used in agricultural production. In our previous work, we found that curcumin analogs exhibit excellent biological activity against plant viruses, especially protective activity. Inspired by these results, the active substructure of pentadienone and quinazoline were spliced to obtain curcumin analogs as potential exogenously induced resistant molecule. Bioassay results showed that compound A13 exhibited excellent protective activity for tobacco to against Tobacco mosaic virus (TMV) at 500 μg/mL, with a value of 70.4 ± 2.6% compared with control treatments, which was better than that of the plant immune activator chitosan oligosaccharide (49.0 ± 5.9%). The protective activity is due to compound A13 inducing tobacco resistance to TMV, which was related to defense-related enzymes, defense-related genes, and photosynthesis. This was confirmed by the up-regulated expression of proteins that mediate stress responses and oxidative phosphorylation. [ABSTRACT FROM AUTHOR]

Mesoionic pyrido[1,2-α]pyrimidinone derivatives containing a neonicotinoid moiety were designed, synthesized, and evaluated for their insecticidal activity. Some of the title compounds showed remarkable insecticidal properties against Aphis craccivora. Compound I13 exhibited satisfactory insecticidal activity against A. craccivora. Meanwhile, label-free proteomics analysis of compound I13 treatment identified a total of 821 proteins. Of these, 35 proteins were up-regulated, whereas 108 proteins were down-regulated. Differential expressions of these proteins reflected a change in cellular structure and metabolism. [ABSTRACT FROM AUTHOR]

Southern rice black-streaked dwarf virus (SRBSDV) has spread from thesouth of China to the north of Vietnam in the past few years and severelyinfluenced rice production. Its long incubation period and early symptoms are not evident; thus, controlling it is difficult. Chitosan oligosaccharide (COS) is a green plant immunomodulator. Early studies showed that preventing and controlling SRBSDV have a certain effect and reduce disease infection rate, but its underlying controlling and preventing mechanism is unclear. In this study, label-free proteomics was used to analyze differentially expressed proteins in rice after COS treatment. The results showed that COS can up-regulate the plant defense-related proteins and down-regulate the protein expression levels of SRBSDV. Meanwhile, quantitative real-time PCR test results showed that COS can improve defense gene expression in rice. Moreover, COS can enhance the defense enzymatic activities of peroxidase, superoxide dismutase and catalase through mitogen-activated protein kinase signaling cascade pathway, and enhance the rice disease resistance., Competing Interests: The authors declare no conflict of interest.

1,4-Pentadien-3-one derivatives derived from curcumin possess excellent inhibitory activity against plant viruses. On the basis of this finding, a series of novel 1,4-pentadien-3-one derivatives containing a 1,3,4-thiadiazole moiety were designed and synthesized, and their structures confirmed by IR, ¹H-NMR, and 13 C-NMR spectroscopy and elemental analysis. The antiviral activities of the title compounds were evaluated against tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV) in vivo. The assay results showed that most of compounds had remarkable antiviral activities against TMV and CMV, among which compounds 4b , 4h , 4i , 4k , 4o , and 4q exhibited good curative, protection, and inactivation activity against TMV. Compounds 4h , 4i , 4k , 4l , 4o , and 4q exhibited excellent protection activity against TMV, with EC 50 values of 105.01, 254.77, 135.38, 297.40, 248.18, and 129.87 μg/mL, respectively, which were superior to that of ribavirin (457.25 µg/mL). In addition, preliminary SARs indicated that small electron-withdrawing groups on the aromatic ring were favorable for anti-TMV activity. This finding suggests that 1,4-pentadien-3-one derivatives containing a 1,3,4-thiadiazole moiety may be considered as potential lead structures for discovering new antiviral agents.

Diseases caused by southern rice black-streaked dwarf virus (SRBSDV) and rice ragged stunt virus (RRSV) considerably decrease grain yield. Therefore, determining rice cultivars with high resistance to SRBSDV and RRSV is necessary. In this study, rice cultivars with high resistance to SRBSDV and RRSV were evaluated through field trials in Shidian and Mangshi county, Yunnan province, China. SYBR Green I-based quantitative real-time polymerase chain reaction (qRT-PCR) analysis was used to quantitatively detect virus gene expression levels in different rice varieties. The following parameters were applied to evaluate rice resistance: acre yield (A.Y.), incidence of infected plants (I.I.P.), virus load (V.L.), disease index (D.I.), and insect quantity (I.Q.) per 100 clusters. Zhongzheyou1 (Z1) and Liangyou2186 (L2186) were considered the most suitable varieties with integrated higher A.Y., lower I.I.P., V.L., D.I. and I.Q., Features: In order to investigate the mechanism of rice resistance, comparative label-free shotgun liquid chromatography tandem-mass spectrometry (LC-MS/MS) proteomic approaches were applied to comprehensively describe the proteomics of rice varieties' SRBSDV tolerance. Systemic acquired resistance (SAR)-related proteins in Z1 and L2186 may result in the superior resistance of these varieties compared with Fengyouxiangzhan (FYXZ).

Studies of the targets of anti-viral compounds are hot topics in the field of pesticide research. Various efficient anti-TMV (Tobacco Mosaic Virus) compounds, such as Ningnanmycin (NNM), Antofine (ATF), Dufulin (DFL) and Bingqingxiao (BQX) are available. However, the mechanisms of the action of these compounds on targets remain unclear. To further study the mechanism of the action of the anti-TMV inhibitors, the TMV coat protein (TMV CP) was expressed and self-assembled into four-layer aggregate disks in vitro, which could be reassembled into infectious virus particles with TMV RNA. The interactions between the anti-TMV compounds and the TMV CP disk were analyzed by size exclusion chromatography, isothermal titration calorimetry and native-polyacrylamide gel electrophoresis methods. The results revealed that assembly of the four-layer aggregate disk was inhibited by NNM; it changed the four-layer aggregate disk into trimers, and affected the regular assembly of TMV CP and TMV RNA. The four-layer aggregate disk of TMV CP was little inhibited by ATF, DFL and BQX. Our results provide original data, as well as new strategies and methods, for research on the mechanism of action of anti-viral drugs.

A series of novel 4-thioquinazoline derivatives containing chalcone moiety were designed, synthesized and systematically evaluated for their antiviral activity against TMV. The bioassay results showed that most of these compounds exhibited moderate to good anti-TMV activity. In particular, compounds M2 and M6 possessed appreciable protection activities against TMV in vivo, with 50% effective concentration (EC50) values of 138.1 and 154.8 μg/mL, respectively, which were superior to that of Ribavirin (436.0 μg/mL). The results indicated that chalcone derivatives containing 4-thioquinazoline moiety could effectively control TMV. Meanwhile, the structure-activity relationship (SAR) of the target compounds, studied using the three-dimensional quantitative structure-activity relationship (3D-QSAR) method of comparative molecular field analysis (CoMFA) based on the protection activities against TMV, demonstrated that the CoMFA model exhibited good predictive ability with the cross-validated q2 and non-cross-validated r2 values of 0.674 and 0.993, respectively. Meanwhile, the microscale thermophoresis (MST) experimental showed that the compound M6 may interaction with the tobacco mosaic virus coat protein (TMV CP).

In this study, sulfone derivatives containing 1,3,4-oxadiazole moieties indicated good antibacterial activities against rice bacterial leaf blight caused by the pathogen Xanthomonas oryzaepv. pv. oryzae (Xoo). In particular, 2-(methylsulfonyl)-5-(4-fluorobenzyl)-1,3,4-oxadiazole revealed the best antibacterial activity against Xoo, with a half-maximal effective concentration (EC50) of 9.89 μg/mL, which was better than those of the commercial agents of bismerthiazole (92.61 μg/mL) and thiodiazole copper (121.82 μg/mL). In vivo antibacterial activity tests under greenhouse conditions and field trials demonstrated that 2-(methylsulfonyl)-5-(4-fluorophenyl)-1,3,4-oxadiazole was effective in reducing rice bacterial leaf blight. Meanwhile, 2-(methylsulfonyl)-5-(4-fluorophenyl)-1,3,4-oxadiazole stimulate the increase in superoxide dismutase (SOD) and peroxidase (POD) activities in rice, causing marked enhancement of plant resistance against rice bacterial leaf blight. It could also improve the chlorophyll content and restrain the increase in the malondialdehyde (MDA) content in rice to considerably reduce the amount of damage caused by Xoo. Moreover, 2-(methylsulfonyl)-5-(4-fluorophenyl)-1,3,4-oxadiazole, at a concentration of 20 μg/mL, could inhibit the production of extracellular polysaccharide (EPS) with an inhibition ratio of 94.52%, and reduce the gene expression levels of gumB, gumG, gumM, and xanA, with inhibition ratios of 94.88%, 68.14%, 86.76%, and 79.21%, respectively.

Southern rice black streaked dwarf virus (SRBSDV) causes severe harm to rice production. Unfortunately, studies on effective antiviral drugs against SRBSDV and interaction mechanism of antiviral molecule targeting on SRBSDV have not been reported. This study found dufulin (DFL), an ideal anti-SRBSDV molecule, and investigated the interactions of DFL targeting on the nonstructural protein P9-1. The biological sequence information and bonding characterization of DFL to four kinds of P9-1 protein were described with fluorescence titration (FT) and microscale thermophoresis (MST) assays. The sequence analysis indicated that P9-1 had highly-conserved C- and N-terminal amino acid residues and a hypervariable region that differed from 131 aa to 160 aa. Consequently, wild-type (WT-His-P9-1), 23 C-terminal residues truncated (TR-ΔC23-His-P9-1), 6 N-terminal residues truncated (TR-ΔN6-His-P9-1), and Ser138 site-directed (MU-138-His-P9-1) mutant proteins were expressed. The FT and MST assay results indicated that DFL bounded to WT-His-P9-1 with micromole affinity and the 23 C-terminal amino acids were the potential targeting site. This system, which combines a complete sequence analysis, mutant protein expression, and binding action evaluating system, could further advance the understanding of the interaction abilities between antiviral drugs and their targets.

An effective method has been developed for the preparation of novel chiral chalcone derivatives under mild conditions from the easily accessible starting materials nitromethane and chalcone derivatives 2. The corresponding products were obtained in moderate yields with excellent enantioselectivities (up to 99%).

An efficient one-pot synthesis of novel β-amino acid derivatives containing a thiadiazole moiety was developed using a chiral squaramide cinchona alkaloid as organocatalyst. The reactions afforded chiral β-amino acid derivatives in moderate yields and with moderate to excellent enantioselectivities. The present study demonstrated for the first time the use of a Mannich reaction catalyzed by a chiral bifunctional organocatalyst for the one-pot synthesis of novel β-amino acid derivatives bearing a 1,3,4-thiadiazole moiety on nitrogen.

A series of N-(substituted pyridinyl)-1-methyl(phenyl)-3-trifluoromethyl-1H-pyrazole-4-carboxamide derivatives were synthesized. All target compounds were characterized by spectral data (¹H-NMR, ¹³C-NMR, IR, MS) and elemental analysis and were bioassayed in vitro against three kinds of phytopathogenic fungi (Gibberella zeae, Fusarium oxysporum, Cytospora mandshurica). The results showed that some of the synthesized N-(substituted pyridinyl)-1-methyl-3-trifluoromethyl-1H-pyrazole-4-carboxamides exhibited moderate antifungal activities, among which compounds 6a, 6b and 6c displayed more than 50% inhibition activities against G. zeae at 100 µg/mL, which was better than that of the commercial fungicides carboxin and boscalid.

An activity-directed fractionation and purification process was used to isolate antitumor compounds from the roots of Belamcanda chinensis (L.) DC. The ethyl acetate extract showed greater antitumor activities than the other extracts, consequently leading to the isolation of 18 compounds identified as β-sitosterol (1), dausterol (2), quercetin (3), kampferol (4), shikimic acid (5), gallic acid (6), ursolic acid (7), betulin (8), betulonic acid (9), betulone (10), tectoridin (11), irisflorentin (12), 4′,5,6-trihydroxy-7-methoxyisoflavone (13), tectorigenin (14), irilins A (15), iridin (16), irigenin (17), and iristectongenin A (18). Compounds 3-10, 13, and 15 were isolated from B. chinensis for the first time. Compounds 4 and 7-10 showed potent cytotoxic activities against PC3, MGC-803, Bcap-37, and MCF-7 cell lines. The mechanism of the antitumor action of compound 7 was preliminarily investigated through acridine orange/ethidium bromide (AO/EB) staining, Hoechst 33258 staining, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, which indicated the growth inhibition of MGC-803 cells via the induction of tumor cell apoptosis.

Sixteen novel pyrazole acyl thiourea derivatives 6 were synthesized from monomethylhydrazine (phenylhydrazine) and ethyl acetoacetate. The key 5-chloro-3-methyl-1-substituted-1H-pyrazole-4-carbonyl chloride intermediates 4 were first generated in four steps through cyclization, formylation, oxidation and acylation. Thess were then reacted with ammonium thiocyanate in the presence of PEG-400 to afford 5-chloro-3-methyl-1-substituted-1H-pyrazole-4-carbonyl isothiocyanates 5. Subsequent reaction with fluorinated aromatic amines resulted in the formation of the title compounds. The synthesized compound were unequivocally characterized by IR, ¹H-NMR, ¹³C-NMR and elemental analysis and some of the synthesized compounds displayed good antifungal activities against Gibberella zeae, Fusarium oxysporum, Cytospora mandshurica and anti-TMV activity in preliminary antifungal activity tests.

This study describes the simple synthesis of new (quinazolin-4-ylamino) methylphosphonates via microwave irradiation. Substituted-2-aminobenzonitrile reacted with 1,1-dimethoxy-N,N-dimethylmethanamine at a reflux condition to obtain N'-(substituted-2-cyanophenyl)-N,N-dimethylformamidine (1). The subsequent reaction of this intermediate product with α-aminophosphonate (2) in a solution containing glacial acetic acid in 2-propanol through microwave irradiation resulted in the formation of (quinazolin-4-ylamino)methyl-phosphonate derivatives 3a to 3x, which were unequivocally characterized by the spectral data and elemental analysis. The influence of the reaction conditions on the yield of 3a was investigated to optimize the synthetic conditions. The relative optimal conditions for the synthesis of 3a include a 1:1 molar ratio of N'-(2-cyanophenyl)-N,N-dimethylformamidine to diethyl amino(phenyl)methylphosphonate and a 4:1 volume ratio of isopropanol to HOAc in the solvent mixture, at a reaction temperature of 150 °C, with a microwave power of 100 W and a corresponding pressure of 150 psi for 20 min in the microwave synthesizer. The yield of 3a was approximately 79%, whereas those of 3b to 3x were approximately 77% to 86%. Some of the synthesized compounds displayed weak to good anti-Tobacco mosaic virus (TMV) activity.

Outbreaks of the southern rice black-streaked dwarf virus (SRBSDV) have caused significant crop losses in southern China in recent years, especially in 2010. There are no effective, quick and practicable methods for the diagnosis of rice dwarf disease that can be used in the field. Traditional reverse transcription-polymerase chain reaction (RT-PCR) methodology is accurate but requires expensive reagents and instruments, as well as complex procedures that limit its applicability for field tests. To develop a sensitive and reliable assay for routine laboratory diagnosis, a rapid dot enzyme-linked immunosorbent assay (dot-ELISA) method was developed for testing rice plants infected by SRBSDV. Based on anti-SRBSDV rabbit antiserum, this new dot-ELISA was highly reliable, sensitive and specific toward SRBSDV. The accuracy of two blotting media, polyvinylidene fluoride membrane (PVDF membrane) and nitrocellulose filter membrane (NC membrane), was compared. In order to facilitate the on-site diagnosis, three county laboratories were established in Shidian (Yunnan province), Jianghua (Hunan Province) and Libo (Guizhou province). Suspected rice cases from Shidian, Yuanjiang and Malipo in Yunnan province were tested and some determined to be positive for SRBSDV by the dot-ELISA and confirmed by the One Step RT-PCR method. To date, hundreds of suspected rice samples collected from 61 districts in southwestern China have been tested, among which 55 districts were found to have rice crops infected by SRBSDV. Furthermore, the test results in the county laboratories showed that Libo, Dehong (suspected samples were sent to Shidian) and Jianghua were experiencing a current SRBSDV outbreak.

Using half-leaf method O,O'-diisopropyl (3-(L-1-(benzylamino)-1-oxo-3- phenylpropan-2-yl)thioureido)(phenyl)methyl phosphonate (2009104) was studied for its activity on tobacco mosaic virus (TMV). It showed good curative activity in vivo and the curative activity at 500 μg/mL was found to be 53.3%. In vivo treatment with the control agent Ningnanmycin at 500 μg/mL resulted in 51.2% inhibition and curative inhibition rates respectively. Dot-ELISA test was employed to verify the efficacy of activity of compound 200910 for anti-TMV activity. The mechanism of action of compound 2009104 to resist TMV was also studied. The results showed that the resistance enzymes PAL, POD, SOD activity and chlorophyll content after TMV inoculation K(326) (Nicotiana tabacum K(326)) of tobacco plants followed by treatment with compound 2009104 were significantly enhanced. The study of the effect of compound 2009104 on TMV capsid protein (CP) showed that it inhibited the polymerization process of TMV-CP in vitro.

Some 3-(Substituted methylthio)-4-phenyl-5-(3,4,5-trimethoxyphenyl)-4H-1,2,4-triazole derivatives were synthesized in six steps starting from easily accessible gallic acid. The resulting sulfides were then catalytically oxidized to the title sulfones with H2O2. The products were obtained in high yield under mild conditions and practically devoid of any by-products. The structures were confirmed by elemental analysis, IR, 1H- and 13C-NMR spectral data. Furthermore, a detailed X-ray crystallography structural analysis of model triazole 7g was carried out.

An effective method has been developed for the preparation under mild conditions of novel pyridazine derivatives from the easily accessible starting materials mucochloric acid and benzene. All the synthesized compounds were fully characterized and some of them displayed good antifungal activities against G. zeae, F. oxysporum and C. mandshurica in preliminary antifungal activity tests.

New alpha-aminophosphonates were synthesized by the Kabachnik-Fields reaction of 3,4,5-trimethoxybenzaldehyde (TMB) with p- or m-bromoaniline and a dialkyl phosphite under solvent-free conditions. TMB was prepared from gallic acid via a four step synthetic sequence involving etherification, esterification, hydrazidation and potassium ferricyanide oxidation. The structures of all synthesized compounds were confirmed by elemental analysis, IR, 1H-, 13C- and 31P-NMR spectral data. Compound 7g was also characterized by X-ray crystallography. A half-leaf method was used to determine the in vivo curative efficacy of the eight title products against tobacco mosaic virus (TMV). It was found that compounds 7g and 7h possess good in vivo curative effects against TMV.

A simple, efficient, and general method has been developed for the synthesis of various alpha-aminophosphonate derivatives 4a-4l by treatment of substituted benzaldehydes and aniline with bis(2-methoxyethyl)- or bis(2-ethoxyethyl) phosphite under microwave irradiation without solvents and catalysts. The products were characterized by elemental analysis, IR, 1H-NMR, 13C- and 31P-NMR spectra. The X-ray crystallographic data of the representative compound 4l was determined. The new alpha-aminophosphonate derivatives were found to possess moderate to good antiviral activity.

A simple, efficient, and general method has been developed for the synthesis of various 3-alkylquinazolin-4-one derivatives from quinazolin-4-one treated with alkyl bromides under phase transfer catalysis condition. The structures of the compounds were characterized by elemental analysis, IR, (1)H-NMR and (13)C-NMR spectra. Title compound 6-bromo-3-propylquinazolin-4-one (3h) was found to possess good antifungal activity.

A simple, efficient, and general method has been developed for the synthesis of various N-aryl heterocylic substituted-4-aminoquinazoline compounds from 4-chloro- quinazoline and aryl heterocyclic amines under microwave irradiation using 2-propanol as solvent. The advantages of the use of microwave irradiation in relation to the classical method were demonstrated.

A facile synthesis of 3-methylthio-3-arylamino-2-cyanoacrylates from 3,3-dimethylthioacrylate and aromatic amines or amino pyridines has been achieved in moderate to high yields (64.0% ~ 93.5%) in 30 minutes at 50 degrees C under microwave irradiation. This method is very simple and the reaction conditions are mild, environmentally friendly and more importantly, quick. In the 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) test, some of the title compounds were found to possess good antiproliferation activity towards PC3 cells.