Showing papers by "Yuxiu Liu published in 2012"

Design, synthesis, and insecticidal activity of novel pyrazole derivatives containing α-hydroxymethyl-N-benzyl carboxamide, α-chloromethyl-N-benzyl carboxamide, and 4,5-dihydrooxazole moieties.

Abstract: On the basis of commercial insecticides tebufenpyrad and tolfenpyrad, two series of novel pyrazole-5-carboxamides containing α-hydroxymethyl-N-benzyl or α-chloromethyl-N-benzyl and pyrazoles containing 4,5-dihydrooxazole moieties were designed and synthesized via the key intermediate 2-amino-1-(4-substituted) phenyl ethanol. The structures of target compounds were confirmed by (1)H NMR and elemental analysis or high-resolution mass spectrum (HRMS), and their activities against cotton bollworm (Helicoverpa armigera), diamondback moth (Plutella xylostella), bean aphid (Aphis craccivora), mosquito (Culex pipiens pallens), and spider mite (Tetranychus cinnabarinus) were tested. The results of bioassays indicated that compounds containing α-chloromethyl-N-benzyl and compounds containing 4,5-dihydrooxazole showed high insecticidal activity against cotton bollworm. Especially, stomach activities of compounds Ij, Il, and IIe were 60% at 5 mg kg(-1). Moreover, the target compounds exhibited high selectivity between cotton bollworm and diamondback moth, although both of them belong to the order Lepidoptera. Although the activities against diamondback moth were at a low level, some of the target compounds exhibited antifeedant activity. The compounds also had good activities against bean aphid, mosquito, and spider mite. The foliar contact activity of compounds Ic, Id, Ie, and IIf against bean aphid were 95, 95, 100, and 95%, respectively, at 200 mg kg(-1). The miticidal and ovicidal activities of compound IIi against spider mite were both 95% at 200 mg kg(-1). Furthermore, a trivial change at 4-position of pyrazole ring would lead to great changes in properties and activities, which can easily be deduced by comparing the activities of compounds in series I (4-chloro-pyrazole compounds) with corresponding compounds in series II (4-hydro-pyrazole compounds), especially from the miticidal and ovicidal activities of Ii and IIi against spider mite.

Design, synthesis, antiviral activity, and SARs of 14-aminophenanthroindolizidines.

Abstract: Based on our previous structure–activity relationship and antiviral mechanism studies, a series of 14-aminophenanthroindolizidines (1a–i, 2, and 3) were designed, targeting tobacco mosaic virus (TMV) RNA, and synthesized and systematically evaluated for their antiviral activity against TMV. The bioassay results showed that most of these compounds exhibited good to excellent in vivo anti-TMV activity, of which compounds 1d and 1h displayed significantly higher activity than commercial ningnanmycin, and thus emerged as potential inhibitors of plant virus. The introduction of amino groups at the 14-position of phenanthroindolizidines, which is proposed to interact with arginine residues around the TMV RNA, increased anti-TMV activity.

A Novel Sodium Nitrite-Catalyzed Oxidative Coupling for Constructing Polymethoxyphenanthrene Rings

Abstract: An efficient and green oxidative coupling for the direct construction of polymethoxyphenanthrene rings has been developed, which uses environment-friendly sodium nitrite as catalyst and oxygen as terminal oxidant. This methodology also provides an alternative possibility for forming biaryl products.

Design, synthesis, and antiviral activity evaluation of phenanthrene-based antofine derivatives.

Abstract: On the basis of our previous structure–activity relationship (SAR) and antiviral mechanism studies, a series of phenanthrene-based antofine derivatives (1–12 and 18–50) were designed targeting tobacco mosaic virus (TMV) RNA and synthesized and systematically evaluated for their antiviral activity against TMV. The bioassay results showed that most of these compounds exhibited good to excellent in vivo anti-TMV activity, of which compounds 19 and 27 displayed higher activity than commercial Ribavirin, thus emerging as potential inhibitors of plant virus. The novel concise structure provides another new template for antiviral studies.

First discovery and stucture-activity relationship study of phenanthroquinolizidines as novel antiviral agents against tobacco mosaic virus (TMV).

Abstract: A series of phenanthroquinolizidine alkaloids 1–24 were prepared and first evaluated for their antiviral activity against tobacco mosaic virus (TMV). The bioassay results showed that most of these compounds exhibited good to excellent in vivo anti-TMV activity, of which compounds 1, 2, 15 and 16 displayed significantly higher activity than (R)-antofine and commercial Ningnanmycin at the same test condition. The substituents on the phenanthrene moiety play an important role for maintaining high in vivo antiviral activity. The introduction of 6-hydroxyl, which is proposed to interact with TMV RNA, did increased anti-TMV activity. The 14aR-configuration was confirmed to be the preferred antiviral configuration for phenanthroquinolizidine alkaloids. Introduction of hydroxy group at 15-position of phenanthroquinolizidine alkaloids increased activity for S-configuration but decreased activity for R-configuration. Present study provides fundamental support for development and optimization of phenanthroquinolizidine alkaloids as potential inhibitors of plant virus.

Therapeutic effects of a novel tylophorine analog, NK-007, on collagen-induced arthritis through suppressing tumor necrosis factor α production and Th17 cell differentiation.

Abstract: Objective To analyze the effects of a novel compound, NK-007, on the prevention and treatment of collagen-induced arthritis (CIA) and the underlying mechanisms. Methods We determined the effect of NK-007 on lipopolysaccharide (LPS)–triggered tumor necrosis factor α (TNFα) production by murine splenocytes and a macrophage cell line (RAW 264.7) by enzyme-linked immunosorbent assay, intracellular cytokine staining, and Western blotting. The LPS-boosted CIA model was adopted, and NK-007 or vehicle was administered at different time points after immunization. Mice were monitored for clinical severity of arthritis, and joint tissues were used for histologic examination, cytokine detection, and immunohistochemical staining. Finally, stability of TNFα production and Th17 cell differentiation were studied using quantitative polymerase chain reaction and flow cytometry. Results NK-007 significantly suppressed LPS-induced TNFα production in vitro. Administration of NK-007 completely blocked CIA development and delayed its progression. Furthermore, treatment with NK-007 at the onset of arthritis significantly inhibited the progress of joint inflammation. Administration of NK-007 also suppressed production of TNFα, interleukin-6 (IL-6), and IL-17A in the joint and reduced percentages of IL-17+ cells among CD4+ and γ/δ T cells in draining lymph nodes. We further demonstrated that NK-007 acted on the stability of TNFα messenger RNA and reduced Th17 cell differentiation. In addition, it significantly inhibited levels of IL-6 and IL-17A in human coculture assay. Conclusion For its effects on the development and progression of CIA and for its therapeutic effect on CIA, NK-007 has great potential to be a therapeutic agent for human rheumatoid arthritis.

Hydroxyl May Not Be Indispensable for Raltegravir: Design, Synthesis and SAR Studies of Raltegravir Derivatives as HIV-1 Inhibitors.

Abstract: A variety of raltegravir derivatives such as (I) and (II) is synthesized and systematically evaluated for their anti-HIV activity.

A Novel Sodium Nitrite Catalyzed Oxidative Coupling for Constructing Polymethoxyphenanthrene Rings.

Abstract: The coupling of polyoxy-substituted benzenes using air as the terminal oxidant provides access towards phenanthrenes and also biphenyl derivatives.