CD44-mediated tumor homing of hyaluronic acid nanogels for hypoxia-activated photodynamic therapy against tumor.

In this study, unique hypoxia-activated hyaluronic acid nanogels (HANGs) were reported for CD44-targeted delivery of photosensitizers (chlorin e6, Ce6) for diagnostic imaging and photodynamic therapy (PDT) of cancers. Through the use of a hypoxia-responsive cross-linker (AZO-CDI), the HANGs were prepared by chemically cross-linking primary amine groups-functionalized hyaluronic acid (HA). Under normoxic condition, fluorescence of Ce6 conjugated on the HANGs was highly quenched, and level of reactive oxygen species (ROS) generated from the HANGs was rather low after laser irradiation.

Dual-targeting multifunctional hyaluronic acid ligand-capped gold nanorods with enhanced endo-lysosomal escape ability for synergetic photodynamic-photothermal therapy of cancer.

Au nanorods (AuNRs) have attracted considerable interest as drug delivery systems because of their enhanced cell internalization and stronger drug-loading ability. In addition, the incorporation of photodynamic therapy (PDT) and photothermal therapy (PTT) into one nanosystem presents great promise to defect multiple drawbacks in cancer therapy. Herein, we fabricated a multifunctional and dual-targeting nanoplatform based on hyaluronic acid-grafted-(mPEG/triethylenetetramine-conjugated-lipoic acid/tetra(4-carboxyphenyl)porphyrin/folic acid) polymer ligand capped AuNRs (AuNRs@HA-g-(mPEG/Teta-co-(LA/TCPP/FA)) for combined photodynamic-photothermal therapy of cancer.

Quantitative structure-activity relationship (QSAR) directed the discovery of 3-(pyridin-2-yl)benzenesulfonamide derivatives as novel herbicidal agents.

Background: Agrochemicals have been crucial to the production of food, and the need for the development of novel agrochemicals continues unceasing owing to the loss of existing produces via the growth of resistance and the desire for products with more propitious environmental and toxicological patterns.

Results: The results of both CoMFA and CoMSIA models indicated that biological activity can effectively be improved through the structural optimisation and molecular design of these synthetic compounds from the aspects of steric, electrostatic, hydrophobic, hydrogen bond donor and acceptor fields. Data of postemergence herbicidal activity in the greenhouse explained that most new 3-(pyridin-2-yl)benzenesulfonamide derivatives (4c-4 t) could control highly effectively against barnyardgrass, foxtail, vetleaf, and youth and old age (herbicidal activity ≥90%); for example, compounds 4q-4 t exhibit excellent biological activity equivalent/superior to commercial saflufenacil/sulcotrione at the low concentration of 37.

Discovery of pyridine-based agrochemicals by using Intermediate Derivatization Methods.

Pyridine-based compounds have been playing a crucial role as agrochemicals or pesticides including fungicides, insecticides/acaricides and herbicides, etc. Since most of the agrochemicals listed in the Pesticide Manual were discovered through screening programs that relied on trial-and-error testing and new agrochemical discovery is not benefiting as much from the in silico new chemical compound identification/discovery techniques used in pharmaceutical research, it has become more important to find new methods to enhance the efficiency of discovering novel lead compounds in the agrochemical field to shorten the time of research phases in order to meet changing market requirements. In this review, we selected 18 representative known agrochemicals containing a pyridine moiety and extrapolate their discovery from the perspective of Intermediate Derivatization Methods in the hope that this approach will have greater appeal to researchers engaged in the discovery of agrochemicals and/or pharmaceuticals.

Design, synthesis and insecticidal evaluation of aryloxy dihalopropene derivatives.

Plutella xylostella (P. xylostella) is a highly migratory, cosmopolitan species and one of the most important pest of cruciferous crops worldwide. Pyridalyl as a novel class of insecticides has good efficacy against P.

Design, synthesis and structure-activity relationship of novel diphenylamine derivatives.

Diphenylamine derivatives have been reported with good fungicidal, insecticidal, acaricidal, rodenticidal and/or herbicidal activities. To find new lead compound of this kind, a series of novel diphenylamine derivatives were designed and synthesized by the approach of Intermediate Derivatization Methods. All compounds were identified by (1)H NMR and elemental analysis.

Synthesis and evaluation of substituted 3-(pyridin-2-yl)benzenesulfonamide derivatives as potent herbicidal agents.

In an attempt to obtain novel candidate compound for weed control, a series of newly substituted 3-(pyridin-2-yl)benzenesulfonamide derivatives 2 were designed and synthesized using compound II7 as a lead compound by Intermediate Derivatization Methods and their herbicidal activities were evaluated. The herbicidal activity assay in greenhouse tests showed several compounds (2g, 2i, 2j, 2k, 2l, 2m, 2n and 2o) exhibited significant herbicidal activity for controlling velvet leaf (Abutilon theophrasti medic.) and youth-and-old age (Zinnia elegans jacq.

Feasibility Study on Quantitative Analysis of Sulfide Concentration and pH of Marine Sediment Pore Water via Raman Spectroscopy.

Marine sediment pore water is one of the important objects in the study of global environmental change, marine geology and biogeochemistry. Anoxic pore water in highly reducing deep-sea sediments commonly contains a large amount of dissolved sulfide (H2S and HS-). The sulfide species within sediment pore water are significant not only because the importance of themselves, but also because they exist as a function of pH which is another key parameter in pore water study.

Design, synthesis, and herbicidal activity of novel substituted 3-(pyridin-2-yl)benzenesulfonamide derivatives.

A series of novel substituted 3-(pyridin-2-yl)benzenesulfonamide derivatives were designed and synthesized using 2-phenylpridines as the lead compound by intermediate derivatization methods in an attempt to obtain novel compound candidates for weed control. The herbicidal activity assay in glasshouse tests showed several compounds (II6, II7, II8, II9, II10, II11, III2, III3, III4, and III5) could efficiently control velvet leaf, youth-and-old age, barnyard grass, and foxtail at the 37.5 g/ha active substance.

Design, synthesis and structure-activity relationship of novel oxime ether strobilurin derivatives containing substituted benzofurans.

Background: Strobilurins are one of the most important classes of agricultural fungicides. To discover new strobilurin analogues with broad spectrum and high activity, a series of novel oxime ether strobilurin derivatives containing substituted benzofurans in the side chain were synthesised and bioassayed.

Results: The synthesised compounds were characterised by (1) H NMR, (13) C NMR, MS and HRMS.

Design, synthesis, and structure-activity relationship of novel aniline derivatives of chlorothalonil.

Chlorothalonil with both low cost and low toxicity is a popularly used fungicide in the agrochemical field. The presence of nucleophilic groups on this compound allows further chemical modifications to obtain novel chlorothalonil derivatives. Fluazinam, another commercially available agent with a broad fungicidal spectrum, has a scaffold of diaryl amine structure.

[Raman spectroscopic investigation of hydrogen storage in nitrogen gas hydrates].

Recently, hydrogen storage using clathrate hydrate as a medium has become a hotspot of hydrogen storage research In the present paper, the laser Raman spectroscopy was used to study the hydrogen storage in nitrogen hydrate. The synthetic nitrogen hydrate was reacted with hydrogen gas under relatively mild conditions (e.g.

Design, synthesis and structure-activity relationship of novel insecticidal dichloro-allyloxy-phenol derivatives containing substituted pyrazol-3-ols.

Background: Pyridalyl, consisting of dicholoro-allyoxy-phenol moiety, is a novel class of insecticide showing extraordinary activities against various lepidopterous and thysanopterous pests on cotton and vegetables. To discover further novel insecticides, a series of new dichloro-allyloxy-phenol derivatives containing substituted pyrazol-3-ol moieties were designed and synthesised via the intermediate derivatisation method.

Results: The target compounds were characterised by (1) H NMR, IR, MS and elemental analysis.

Synthesis and bioactivity of novel coumarin derivatives.

A series of coumarin derivatives (6-8) containing (E)-methyl 2-(methoxyimino)-2-phenylacetate, (E)-2-(methoxyimino)-N-methyl-2-phenylacetamide and methyl methoxy(phenyl)carbamate were synthesized from substituted resorcinols (1) and substituted beta-keto esters (2) as starting material via cyclization and condensation reactions. The test results indicated that (E)-methyl 2-{2-[(3-hexyl-4-methyl-coumarin-7-yloxy)methyl]phenyl}-2-(methoxyimino)acetate (6f) was the optimal structure with good fungicidal activity against cucumber grey mold (CGM) giving 100% control at 100 mg L(-1) concentration, much higher than that of coumoxystrobin. Methyl 2-[(3,4-dimethyl-coumarin -7-yloxy)methyl]phenyl(methoxy)carbamate (8a) was another optimal structure with good fungicidal activity against wheat powdery mildew (WPM) showing 100% control at 50 mg L(-1) concentration, at the same level as that of the commercial kresoxim-methyl, and very significantly higher than that of coumoxystrobin (no control against WPM at 400 mg L(-1)).

[In situ Raman spectroscopic observation of micro-processes of methane hydrate formation and dissociation].

Micro laser Raman spectroscopic technique was used for in situ observation of the micro-processes of methane hydrate formed and decomposed in a high pressure transparent capillary. The changes in clathrate structure of methane hydrate were investigated during these processes. The results show that, during hydrate formation, the Raman peak (2 917 cm(-1)) of methane gas gradually splits into two peaks (2 905 and 2 915 cm(-1)) representing large and small cages, respectively, suggesting that the dissolved methane molecules go into two different chemical environments.

The discovery of SYP-10913 and SYP-11277: novel strobilurin acaricides.

Background: As previously reported, methyl (E)-2-[2-(2-phenylamino-6-trifluoromethylpyrimidin-4-yloxymethyl)phenyl]-3-methoxyacrylate has proven to be a new lead with highly acaricidal activity. Following on from this, in an effort to discover new strobilurin analogues with improved activity, a series of substituted pyrimidines were synthesised and bioassayed.

Results: All compounds were characterised by (1) H NMR, IR, MS and elemental analysis.

Design, synthesis and structure-activity relationship of novel coumarin derivatives.

Background: The lead coumarin derivative (E)-methyl 3-methoxy-2-[2-(4-methylcoumarin-7-yloxymethyl)phenyl]acrylate was discovered by using an intermediate derivatisation method. To discover new coumarin derivatives with improved activity, a series of substituted coumarins were synthesised and bioassayed.

Results: The compounds were identified by ¹H NMR, IR, MS and elemental analysis.

[Association between HLA-DQA1 gene polymorphism and the outcomes of hepatitis B virus infection].

Objective: To investigate the association between HLA-DQA1 gene polymorphism and the outcomes of hepatitis B virus infection in Chinese Han population.

Methods: A total of 180 consecutive patients with biopsy-proven hepatitis B virus infection (120 patients with chronic hepatitis B and 60 patients with asymptomatic HBV carrier) and 60 subjects who resolved from HBV infection spontaneously were studied. Genotype of human leukocyte antigen(HLA)-DQA1 was detected by polymerase chain reaction sequence specific primer(PCR-SSP).

Design, synthesis and acaricidal activity of novel strobilurin derivatives containing pyrimidine moieties.

Background: The intermediate derivatisation method based on bioisosteric replacement led to the discovery of the lead strobilurin compound 5a. To produce new strobilurin analogues with improved activity, a series of substituted pyrimidines were synthesised and bioassayed.

Results: The compounds were identified by (1)H NMR, IR, MS and elemental analysis.

[Determination of hydration number of methane hydrates using micro-laser Raman spectroscopy].

Methane hydrates are clathrate compounds that are formed by methane molecules and water molecules under low temperature and high pressure conditions. It was found that methane hydrates exist widely in sea-shelf floor and permafrost, and are considered as a potential energy resource. In the crystal lattice of clathrate hydrate, the water molecules form both large cages (5(12)6(2)) and small cages (5(12)) under the interaction of the hydrogen-hydrogen bond.

Synthesis and biological activity of new (E)-alpha-(Methoxyimino)benzeneacetate derivatives containing a substituted pyrazole ring.

Strobilurins are one of the most important classes of agricultural fungicides. To discover new strobilurin analogues with high activity, a series of new strobilurin derivatives containing a substituted pyrazole in the side chain were synthesized and their biological activities were tested. The compounds were identified by (1)H nuclear magnetic resonance, infrared, and elemental analysis.

Design, synthesis and biological activity of new strobilurin derivatives with a 1H-pyrazol-5-oxy side chain.

A series of new strobilurin derivatives with a substituted pyrazole side chain (5 and 6) were designed and synthesized. The new derivatives were synthesized from substituted phenones as starting material via esterification, cyclization and condensation reactions. All compounds were identified by 1H NMR and IR spectral and elemental analyses.

Design, synthesis and fungicidal activity of novel strobilurin analogues containing substituted N-phenylpyrimidin-2-amines.

A series of novel compounds (5-8) was designed and synthesized by integrating the active pharmacophore of the N-phenylpyrimidin-2-amine fungicide with the structure of strobilurin fungicide. The rationale of this approach was to determine if these new compounds exhibit unique biological activity (selectivity and potency) compared with the commercial standards. The title compounds were prepared from 2-(phenylamino)pyrimidin-4-ols (3) by treatment with one equivalent of intermediates (4) containing strobilurin pharmacophores.

Photodegradation of flumorph in aqueous solutions and natural water under abiotic conditions.

Flumorph is an oomycete fungicide that is now used extensively in China (Hu, J. Y.; Liu, C.

Design, synthesis and biological activities of new strobilurin derivatives containing substituted pyrazoles.

Background: Strobilurins are one of the most important classes of agricultural fungicides. To discover new strobilurin analogues with high activity, a series of new strobilurin derivatives containing substituted pyrazoles in the side chain were synthesised and bioassayed.

Results: The compounds were identified by (1)H NMR, IR, MS and elemental analysis.