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1.
J Asian Nat Prod Res ; : 1-10, 2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33550877

RESUMO

Eighteen novel 3/5(3,5)-(di)nitropaeonol hydrazone derivatives were prepared, and their structures well characterized by 1H NMR, HRMS, and mp. Due to the steric hindrance, the substituents on the C = N double bond of all hydrazine compounds (except E/Z = 4/1 for IV-1g, IV-1l, IV-2b, and E/Z = 3/2 for IV-1n, IV-3a) adopted E configuration. Among all compounds, four compounds 2, 4, IV-1j, and IV-1n exhibited potent nematicidal activity than their precursor paeonol, especially 5-nitropaeonol (2) and 3,5-dinitropaeonol (4) displayed the most potent nematicidal activity Heterodera glycines in vivo with LC50 values of 32.3307 and 36.7074 mg/L, respectively.

2.
J Mass Spectrom ; : e4529, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32419269

RESUMO

Owing to the poor fragmentation efficiency caused by the lack of a positively charged basic group at the C-termini of peptides, the identification of nontryptic peptides in classical proteomics is known to be less efficient. Particularly, attaching positively charged basic groups to C-termini via chemical derivatizations is known to be able to enhance their fragmentation efficiency. In this study, we introduced a novel strategy, C-termini sequential amidation reaction (CSAR), to improve peptide fragmentation efficiency. By this strategy, C-terminal and side-chain carboxyl groups were firstly amidated by neutral methylamine (MA), and then C-terminal amide bonds were selectively deamidated through peptide amidase while side-chain amide bonds remained unchanged, followed by the secondary amidation of C-termini via basic agmatine (AG). We optimized the amidation reaction conditions to achieve the MA derivatization efficiency of >99% for side-chain carboxyl groups and AG derivatization efficiency of 80% for the hydrolytic C-termini. We applied CSAR strategy to identify bovine serum albumin (BSA) chymotryptic digests, resulting in the increased fragmentation efficiencies (improvement by 9-32%) and charge states (improvement by 39-52%) under single or multiple dissociation modes. The strategy described here might be a promising approach for the identification of peptides that suffered from poor fragmentation efficiency.

3.
J Asian Nat Prod Res ; : 1-11, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32406756

RESUMO

Two series of sulfonate derivatives of carvacrol and thymol were synthesized and screened in vitro for their anti-oomycete activity against Phytophthora capsici, respectively. Among all of 32 derivatives, five compounds 3a, 4a, 4k, 3n, and 4n exhibited more potent anti-oomycete activity against P. capsici with EC50 values of 66.66, 62.94, 68.65, 61.24, and 52.91 mg/L, respectively. This suggested that introduction of different substitutions at the hydroxyl position of 1/2 could have remarkable effect on anti-oomycete activity. Overall, when R1 = isopropyl and R2 = methyl, the anti-oomycete activities of the compounds were higher than that of the corresponding compounds of R1 = methyl and R2 = isopropyl.[Formula: see text].

4.
J Asian Nat Prod Res ; : 1-13, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32091234

RESUMO

Endeavor to discover biorational natural products-based insecticides, two series (27) of novel 9R/S-acyloxy derivatives of cinchonidine and cinchonine were prepared and assessed for their insecticidal activity against Mythimna separata in vivo by the leaf-dipping method at 1 mg/mL. Among all the compounds, especially derivatives 6l and 6o exhibited the best insecticidal activity with final mortality rates of 75.0% and 71.4%, respectively. Overall, a free 9-hydroxyl group is not a prerequisite for insecticidal activity and C9-substitution is well tolerated; the configuration of C8/9 position is important for insecticidal activity, and 9S-configuration is optimal; 6'-OCH3 moiety is not necessary, removal of it is also acceptable.

5.
J Asian Nat Prod Res ; : 1-12, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32009450

RESUMO

Three series of sulfonate derivatives of paeonol were synthesized and screened in vitro for their anti-oomycete activity against P. capsici, respectively. Among all the compounds, 4m displayed the best promising and pronounced anti-oomycete activity against P. capsici than zoxamide, with the EC50 values of 24.51 and 26.87 mg/L, respectively. The results show that acetyl and 4-OCH3 are two necessary groups. The existence of these two sites is closely related to the anti-oomycete activity. Relatively speaking, hydroxyl group is well tolerated, and the results showed that after modification of hydroxyl group with sulfonyl, the anti-oomycete activity was significantly increased.[Formula: see text].

6.
Comb Chem High Throughput Screen ; 23(3): 232-238, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31985371

RESUMO

BACKGROUND: Plant secondary metabolites play an essential role in the discovery of novel insecticide due to their unique sources and potential target sites. Paeonol, the main phenolic components in Moutan Cortex, is recognized as a safe and potent botanical insecticide to many insects. The structural modification of paeonol in this study into phenylsulfonylhydrazone derivatives is proved an effective approach for the development of novel insecticides, those derivatives being more toxic than paeonol. However, there have been no reports on the insecticidal activity of paeonol-based phenylsulfonylhydrazone derivatives in controlling Mythimna separata. METHODS: We have been working to discover biorational natural products-based insecticides. Twelve novel paeonol-based phenylsulfonylhydrazone derivatives have been successfully prepared by structural modification of paeonol, and the insecticidal activity against M. separata by the leafdipping method at the concentration of 1 mg/mL has been evaluated. RESULTS: Insecticidal activity revealed that out of 12 title compounds, derivatives 5c and 5f displayed the best against M. separate with the FMR both of 53.6% than toosendanin (FMR = 50.0%). CONCLUSION: The results suggested that for the paeonol-based phenylsulfonylhydrazone series derivatives, the proper substituent of arylsulfonyl R at the hydroxyl position of paeonol was very important for their insecticidal activity. These preliminary results will pave the way for further modification of paeonol in the development of potential new insecticides.

7.
J Asian Nat Prod Res ; 22(12): 1197-1206, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31773971

RESUMO

Gramine can be intelligently and efficiently supplied with N, N-dimethylamino group and then reacted with the corresponding sulfonyl chlorides to synthesize N, N-dimethylarylsulfonamides. We herein designed and controlled synthesis of N, N-dimethylarylsulfonamide derivatives, and first reported the results of the nematicidal activity of 15 title compounds 3a-o against Meloidogyne incongnita in vitro, respectively. Among all of the title derivatives, compounds 3a, 3c, 3k, and 3o exhibited potent nematicidal activity with median lethal concentration (LC50) values ranging from 0.22 to 0.26 mg/L. Most noteworthy, N, N-dimethyl-4-methoxyphenylsulfonamide (3c) and N, N-dimethyl-8-quinolinesulfonamide (3o) showed the best promising and pronounced nematicidal activity, with LC50 values of 0.2381 and 0.2259 mg/L, respectively.


Assuntos
Antinematódeos , Tylenchoidea , Animais , Antinematódeos/farmacologia , Estrutura Molecular
8.
J Asian Nat Prod Res ; 22(6): 578-587, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31046458

RESUMO

Sixteen sulfonate derivatives of maltol were synthesized and screened in vitro for their anti-oomycete and nematicidal activity against Phytophthora capsici and Bursaphelenchus xylophilus, respectively. Among all the compounds, 3e, 3m, and 3p exhibited the most promising and pronounced anti-oomycete activity against P. capsici than zoxamide, and the EC50 values of 25.42, 18.44, 23.69, and 27.99 mg/L, respectively; compounds 3e, 3m, 3n, and 3p exhibited potent nematicidal activity with LC50 values ranging from 1 to 2 mg/L, especially 3m and 3n showed the best promising and pronounced nematicidal activity, with LC50 values of 1.1762 and 1.2384 mg/L, respectively. [Formula: see text].


Assuntos
Phytophthora , Antinematódeos , Estrutura Molecular , Pironas
9.
J Asian Nat Prod Res ; 22(7): 678-688, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31120307

RESUMO

A series of sulfonate derivatives of sesamol were synthesized and evaluated for their insecticidal activity against a crop-threatening agricultural pest, the pre-third-instar larvae of Mythimna separata in vivo. Among all the target compounds, compounds 3b, 3g, 3h, and 3p exhibited more promising insecticidal activity than sesamol and toosendanin, and the final mortality rates (FMRs) of 3b, 3g, 3h, 3p, 1, and toosendanin were 60.7%/60.7%/67.9%/53.6%/32.1%/50.0%, respectively. Especially compound 3h exhibited the most potent insecticidal activity with FMRs of 67.9%. This suggested that a 4-fluorophenylsulfonyl group introduced at the hydroxyl position of sesamol was necessary for obtaining the most potent compound.[Formula: see text].


Assuntos
Inseticidas , Mariposas , Animais , Benzodioxóis , Larva , Estrutura Molecular , Fenóis
10.
Int J Biol Macromol ; 136: 1060-1068, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31202848

RESUMO

Gluconic acid (GA) and its alkali salts are extensively used in the food, feed, beverage, textile, pharmaceutical and construction industries. However, the cost-effective and eco-friendly production of GA remains a challenge. The biocatalytic process involving the conversion of glucose to GA is catalysed by glucose oxidase (GOD), in which the catalytic efficiency is highly dependent on the GOD stability. In this study, we used in silico design to enhance the stability of glucose oxidase from Aspergillus niger. A combination of the best mutations increased the apparent melting temperature by 8.5 °C and significantly enhanced thermostability and thermoactivation. The variant also showed an increased optimal temperature without compromising the catalytic activity at lower temperatures. Moreover, the combined variant showed higher tolerance at pH 6.0 and 7.0, at which the wild-type enzyme rapidly deactivated. For GA production, an approximate 2-fold higher GA production yield was obtained, in which an almost complete conversion of 324 g/L d-glucose to GA was achieved within 18 h. Collectively, this work provides novel and efficient approaches for improving GOD thermostability, and the obtained variant constructed by the computational strategy can be used as an efficient biocatalyst for GA production at industrially viable conditions.


Assuntos
Aspergillus niger/enzimologia , Gluconatos/metabolismo , Glucose Oxidase/metabolismo , Engenharia de Proteínas , Temperatura , Biocatálise , Estabilidade Enzimática/genética , Fermentação , Glucose Oxidase/química , Glucose Oxidase/genética , Concentração de Íons de Hidrogênio , Modelos Moleculares , Mutação , Conformação Proteica
11.
J Asian Nat Prod Res ; 21(10): 1028-1041, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29974799

RESUMO

As our ongoing work on research of natural-product-based insecticidal agents, some 4α/ß-acyloxypodophyllotoxin derivatives were synthesized, and were evaluated against the pre-third-instar larvae of B. mori, A. dissimilis and M. separate in vivo at the concentration of 1 mg ml-1, respectively. Among all derivatives, compounds 2 g, h and 4c, d showed more promising insecticidal activities than their precursors - podophyllotoxin and epipodophyllotoxin. Furthermore, derivatives 2 g, h and 4c, d exhibited more relative amicable activities than their precursors - podophyllotoxin and epipodophyllotoxin. This results indicated that 4ß-acyloxy moiety in the podophyllotoxin derivatives was significant for obtaining the more potent compounds.


Assuntos
Inseticidas/síntese química , Inseticidas/farmacologia , Podofilotoxina/análogos & derivados , Podofilotoxina/síntese química , Animais , Produtos Biológicos , Bombyx , Insetos , Larva , Estrutura Molecular , Podofilotoxina/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade
12.
Nat Chem Biol ; 14(7): 664-670, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29785057

RESUMO

Introduction of innovative biocatalytic processes offers great promise for applications in green chemistry. However, owing to limited catalytic performance, the enzymes harvested from nature's biodiversity often need to be improved for their desired functions by time-consuming iterative rounds of laboratory evolution. Here we describe the use of structure-based computational enzyme design to convert Bacillus sp. YM55-1 aspartase, an enzyme with a very narrow substrate scope, to a set of complementary hydroamination biocatalysts. The redesigned enzymes catalyze asymmetric addition of ammonia to substituted acrylates, affording enantiopure aliphatic, polar and aromatic ß-amino acids that are valuable building blocks for the synthesis of pharmaceuticals and bioactive compounds. Without a requirement for further optimization by laboratory evolution, the redesigned enzymes exhibit substrate tolerance up to a concentration of 300 g/L, conversion up to 99%, ß-regioselectivity >99% and product enantiomeric excess >99%. The results highlight the use of computational design to rapidly adapt an enzyme to industrially viable reactions.


Assuntos
Aspartato Amônia-Liase/química , Biologia Computacional , Aminação , Aspartato Amônia-Liase/metabolismo , Bacillus/enzimologia , Biocatálise
13.
Appl Microbiol Biotechnol ; 102(8): 3675-3685, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29500753

RESUMO

Xylanases, which cleave the ß-1,4-glycosidic bond between xylose residues to release xylooligosaccharides (XOS), are widely used as food additives, animal feeds, and pulp bleaching agents. However, the thermally unstable nature of xylanases would hamper their industrial application. In this study, we used in silico design in a glycoside hydrolase family (GH) 11 xylanase to stabilize the enzyme. A combination of the best mutations increased the apparent melting temperature by 14 °C and significantly enhanced thermostability and thermoactivation. The variant also showed an upward-shifted optimal temperature for catalysis without compromising its activity at low temperatures. Moreover, a 10-fold higher XOS production yield was obtained at 70 °C, which compensated the low yield obtained with the wild-type enzyme. Collectively, the variant constructed by the computational strategy can be used as an efficient biocatalyst for XOS production at industrially viable conditions.


Assuntos
Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/metabolismo , Microbiologia Industrial , Neocallimastix/enzimologia , Estabilidade Enzimática/genética , Biblioteca Gênica , Neocallimastix/genética , Temperatura
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