CHEMICAL PAPERS
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2022
·Vol. 76
·期 4
·2145-2152
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IF 2.146
Zhu Xingji,Kou Xinhui
We disclose a metal-free catalyst system of organic bases/protic acids for effective fully alternating copolymerization of cyclohexene oxide and phthalic anhydride. A series of commercial organic bases and protic acids were employed as binary catalysts, and the effects of different kinds and ratios of organic bases and protic acids were performed to find optimal conditions for achieving the highest catalytic performance. And our results indicated that DMAP/DPP showed higher activity (TOF = 574 h −1 at 140 °C) and perfectly alternating selectivity (ester > 99%), producing polymers with narrow polydispersity (Ð = 1.08 ~ 1.22). Moreover, analysis of the resultant polymers was confirmed by GPC, NMR spectra and MALDI-TOF MS techniques which revealed that P(PA- alt -CHO) polyester with well-defined alternating structure without formation of polyether and DMAP can act as an initiator in DMAP/DPP catalyst system, resulting more effective ring-opening alternating copolymerization. However, trace amount of phthalic acid as an impurity in the system also acted as a bifunctional initiator influencing the molecular weight of the polymer. In addition, the DMAP/DPP catalytic system remained stable at high temperature and the development of this simple catalytic process provided a new chance to exploit in organocatalyzed polymerization.
研究领域:
高分子化学
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有机催化
✓ 已验证
DOI
高影响因子
SEPARATION SCIENCE AND TECHNOLOGY
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2015
·
IF 1.171
Yuanchao Pei,Jianzhou Zhang,Xinxin Song,Ming Zhao,Jianji Wang
In this paper, a series of ionic liquids (ILs) contains cholinium as cations were prepared. These ILs were used as extractants to separate some model drug molecules. The partition coefficients of these drug molecules between ILs and aqueous solutions were determined. Furthermore, the influence of different extraction parameters was investigated: volume ratio, equilibrium time, pH values, temperature, and ILs structure. It is shown that these ILs are highly effective materials for the extraction of drug molecules. The results imply that these ILs may have potential in drug extraction or separation as a new type of media.
研究领域:
药学
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化学
✓ 已验证
DOI
高影响因子
DRUG DELIVERY
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2019
·
IF 3.829
Yujia Zhang,Nan Zhang,Hui Song,He Li,Jin Wen,Xiaochuan Tan,Wensheng Zheng
Gout is a kind of joint disease characterized by the accumulation of monosodium urate (MSU) crystals in the joint and its surrounding tissue, causing persistent hyperuricemia. Colchicine is the first choice of treatment for acute gout attacks. Due to strong toxicity of colchicines oral tablets, there are high fluctuations of blood drug concentration and serious irritation of gastrointestinal tract, and hence a transdermal preparation can help to slow down the blood drug concentration, reduce the frequency of drug taking, and improve the patients' compliance of the drug. The ethosome is a lipid carrier with high concentration of ethanol and has been proved to promote the penetration of drugs into the skin. Borneol (BO) is an excellent penetration enhancer in Chinese medicine, which can promote the entry of drugs into the skin. This paper prepared the borneol-physically-modified colchicine ethosome (COL-bpES) and used the prepared borneol-dioleoyl phosphoethanloamine (BO-DOPE) to prepare borneol-chemically-modified colchicine ethosome (COL-bcES). Compared to the free colchicine aqueous solution (free COL) and normal colchicine ethosome (COL-ES), the borneol-modified colchicine ethosome (COL-bES) demonstrated better drug penetration effect, while the particle size of the COL-bcES was lower than that of the COL-bpES. Toxicity, in vitro diffusion, pharmacokinetics and pharmacodynamics are superior to those of COL-bpES, providing a better delivery system for the treatment of small molecule inflammatory drugs.
研究领域:
药剂学
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Bioresources and Bioproducts
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2021
·
IF 0
Jingwen Shao,Yong Ni,Lifeng Yan
Furfural is an alternative feedstock and has been used for the production of maleic acid (MA) and fumaric acid (FA) by an oxidation process. Deep eutectic solvents (DESs) were used as the green solvents while sodium chlorate was used as an oxidant and vanadium pentoxide was used as the catalyst at 70–90 °C under atmospheric pressure. It was found that several acidic DESs are valid, such as acetic acid/choline chloride (AA/ChCl) and propionic acid/choline chloride (PA/ChCl), and AA/ChCl DES was selected as the solvent for the conversion. The optimal DES is AA/ChCl, and the effect of the amount of oxidant, time, and temperature on the yield of the MA and FA has been systematically studied, and the conversion of furfural can reach 100% while the yield of the MA and FA reached 66.5% under reaction temperature of 80 °C for 12 h, which provides a new green route to synthesis valuable monomers from furfural.
研究领域:
化学工程
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绿色化学
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有机合成
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催化
✓ 已验证
DOI
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 11
·3344-3350
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IF 4
Wenhao Liu,Ming-Hsien Lee,Ruixin Guo,Jiyong Yao
Rare earth borates, a subset of the essential nonlinear optical (NLO) materials, have sparked a significant amount of attention in recent years. In self-fluxing systems, two non-centrosymmetric scandium borates with classical B5O10 groups, namely Rb7SrSc2B15O30 (I) and Rb7CaSc2B15O30 (II), were successfully discovered. Both I and II exhibit a short ultraviolet (UV) cutoff edge (<200 nm) and appropriate second-harmonic generation efficiency (∼0.76 × KH2PO4, ∼0.88 × KH2PO4 at 1064 nm, respectively). According to theoretical calculations, it is speculated that the band gap and NLO characteristics of these two compounds are mostly derived from the B5O10 group and the ScO6 octahedron. Due to the short cutoff edges of I and II, they may be considered as potential NLO materials in the UV and even deep UV spectral ranges. Furthermore, the advent of I and II adds to the diversity of rare earth borates.
研究领域:
无机化学
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材料科学
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固体化学
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非线性光学
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晶体工程
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紫外光功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
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2019
·
IF 4.027
Yu-Heng Hu,Jie Yang,Yun Zhang,Ke-Chun Liu,Teng Liu,Jie Sun,Xiao-Jing Wang
The work is focused on the design of drugs that prevent and treat Alzheimer’s disease (AD) and its complications. A series of 3–(4-aminophenyl)-coumarin derivatives designed, synthesised, fully characterised and evaluated in vitro/vivo. The biological assay experiments showed that some compounds displayed a clearly selective inhibition for acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Among all compounds, compound 4m exhibited the highest AChE inhibition with an IC50 value of 0.091 ± 0.011 µM and compound 4k exhibited the highest BuChE inhibition with an IC50 value of 0.559 ± 0.017 µM. A zebrafish behaviour analyser (Zebrobox) was used to determine the behavioural effects of the active compound on the movement distance of the aluminium chloride-induced zebrafish. Compound 4m offered a potential drug design concept for the development of therapeutic or preventive agents for AD and its complications.
研究领域:
药理学
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神经科学
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药物设计
✓ 已验证
DOI
PubMed
高影响因子
FARADAY DISCUSSIONS
·
2017
·Vol. 201
·63-70
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IF 3.588
Nian Zhao,Ping Li,Xin Mu,Chuanfang Liu,Fuxing Sun,Guangshan Zhu
A novel ultra-stable metal–organic framework, MCIF-1, [Cu2(DCI)2](MeCN), based on dicyanoimidazole and Cu(I), has been synthesized at room temperature successfully. MCIF-1 shows excellent water stability and can retain crystallinity after soaking in water for about one week. In addition, MCIF-1 also shows exceptional resistance under both acidic and basic conditions within a large pH range from 0 to 13.5. What is more, after modifying the synthesis procedure slightly, we can produce this material in a large scale during a very short time. Mild synthesis conditions, excellent stability and ease of large scale production give MCIF-1 great potential for practical use.
研究领域:
材料科学
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无机化学
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纳米技术
✓ 已验证
DOI
高影响因子
PLANT PHYSIOLOGY AND BIOCHEMISTRY
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2018
·
IF 2.718
Chen Geng,Tengfei Zhao,Chunxian Yang,Qiaozhuo Zhang,Feng Bai,Junlan Zeng,Fangyuan Zhang,Xiaoqiang Liu,Xiaozhong Lan,Min Chen,Zhihua Liao
N -methylputrescine is the precursor of nicotine and pharmaceutical tropane alkaloids such as hyoscyamine . Putrescine N -methyltransferase (PMT) catalyzes the N -methylation of putrescine to form N -methylputrescine. While the role of PMT in nicotine biosynthesis is clear, knowledge of PMT in the biosynthesis of tropane alkaloids (TAs) and the regulation of polyamines remains limited. We characterized a PMT gene from Hyoscyamus niger , designated HnPMT that was specifically expressed in roots, especially in the secondary roots and dramatically induced by methyl jasmonate (MeJA). The GUS gene was specifically expressed in Arabidopsis roots or in the vascular tissues , including pericycles and endodermis , of the H. niger hairy root cultures , when it was driven by the 5′-flanking promoter region of HnPMT . The recombinant HnPMT was purified for enzymatic assays. HnPMT converted putrescine to form N -methylputrescine, as confirmed by LC-MS. The kinetics analysis revealed that HnPMT had high affinity with putrescine but low catalytic activity, suggesting that it was a rate-limiting enzyme . When HnPMT was suppressed in the H. niger plants by using the VIGS approach, the contents of N -methylputrescine and hyoscyamine were markedly decreased, but the contents of putrescine, spermidine and a mixture of spermine and thermospermine were significantly increased; this suggested that HnPMT was involved in the biosynthesis of tropane alkaloids and played a competent role in regulating the biosynthesis of polyamines . Functional identification of HnPMT facilitated the understanding of TA biosynthesis and thus implied that the HnPMT-catalyzed step might be a target for metabolic engineering of the TA production in H. niger .
研究领域:
植物学
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代谢工程
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分子生物学
✓ 已验证
DOI
高影响因子
JOURNAL OF PHARMACY AND PHARMACOLOGY
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2012
·Vol. 65
·期 1
·149-155
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IF 2.175
Zhang Yan-Hui,Zhang You-Jin,Guo Yan-Lei,Li Wen-Juan,Yu Chao
ObjectivesWith the growing popularity of herbal and natural medicinal products, attention has turned to possible interactions between these products and pharmaceutical drugs. In this study, we examined whether astragaloside IV (AGS-IV) could inhibit the activity of CYP1A2 in rat liver microsomes in vitro and in vivo.MethodsThe effect of AGS-IV on CYP1A2 activity was investigated using probe substrates: phenacetin in vitro and theophylline in vivo. Phenacetin was incubated in rat liver microsomes with or without AGS-IV, and the mechanism, kinetics and type of inhibition were determined. The inhibitory effect of AGS-IV on CYP1A2 activity in rats was also determined using theophylline in vivo. The pharmacokinetics of theophylline were observed after a single or week-long treatment with AGS-IV.Key findingsAGS-IV was found to be a competitive inhibitor with a Ki value of 6.29 μm in vitro. In the multiple-pretreatment rat group, it was found to have a significantly higher area under the concentration–time curve (AUC) for theophylline, as well as a lower apparent oral total body clearance value (CL/F). In contrast, no significant difference in metabolism of theophylline was found for the single pretreatment group.ConclusionsThese findings suggest that AGS-IV is a potent inhibitor of CYP1A2. This work offers a useful reference for the reasonable and safe use of clinically prescribed herbal or natural products to avoid unnecessary herb–drug interactions.
研究领域:
药理学
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中药学
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代谢酶研究
✓ 已验证
DOI
高影响因子
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
·
2024
·Vol. 90
·期 9
·
IF 3.9
Wenmin Chai,Xianbing Mao,Chunfeng Li,Liancai Zhu,Zongyi He,Bochu Wang
Parasites can manipulate host behavior to facilitate parasite transmission. One such host–pathogen interaction occurs between the fungus Ophiocordyceps sinensis and the ghost moth Thitarodes xiaojinensis. O. sinensis is involved in the mummification process of infected host larvae. However, the underlying molecular and chemical mechanism for this phenomenon is unknown. We characterized the small molecules regulating host behaviors and the altered metabolites in infected and mummified host larvae. Lipid-related metabolites, such as phosphatidylcholine, were identified in infected and mummified larvae. Decreased levels of the neurotransmitter acetylcholine (ACh) and elevated choline levels were observed in the brains of both the infected and mummified larvae. The aberrant activity of acetylcholinesterase (AChE) and relative mRNA expression of ACE2 (acetylcholinesterase) may mediate the altered transformation between ACh and choline, leading to the brain dysfunction of mummified larvae. Caspofungin treatment inhibited the mummification of infected larvae and the activity of AChE. These findings indicate the importance of ACh in the mummification of host larvae after O. sinensis infection.
研究领域:
真菌学
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神经生物学
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代谢组学
✓ 已验证
DOI
高影响因子
JOURNAL OF PHYSICS D-APPLIED PHYSICS
·
2021
·Vol. 54
·期 37
·375101
·
IF 3.207
Min Yang,Yujia Yan,Enzhou Liu,Jun Fan,Xiaoyun Hu
As a typical sulfide bimetallic semiconductor material, AgInS2 has been widely studied for its excellent photoelectrochemical properties. However, due to the large lattice mismatch, it is difficult to obtain AgInS2 single phase nanocrystals by conventional reaction. Therefore, the ligand and pH were selected and adjusted for the preparation of AgInS2 single phase nanocrystals. Adding organic molecules containing sulfhydryl groups as ligands could combine with metal ions to form covalent bonds, while OH− could react with transition metal ions to form soluble metal hydroxides, which could protect metal ions from direct reaction with S2−. With the help of x-ray powder diffraction, AgInS2 single phase nanocrystals were successfully prepared by hydrothermal reaction at 180 °C with L-cysteine (L-Cys) or glutathione as the ligand in an alkaline environment. Finally, it was determined that the AgInS2 single phase nanocrystals obtained when the ligand was L-Cys and the reaction time was locked to 24 h had high catalytic activity as determined by a rhodamine B (RhB) removal experiment. In addition, AgInS2/TiO2 (AIS-TO) heterojunction photocatalysts were prepared by an in-situ hydrothermal method to improve the photocatalytic activity of TiO2. Among them, the 5% AIS-TO sample showed the highest catalytic activity, and the degradation rate of RhB was 2.4 times that of TiO2. It was also proved that electrons were transported by a Z-type mechanism in the AIS-TO heterojunction photocatalytic system. This work would provide a feasible scheme for the preparation of more sulfide bimetallic semiconductor single phase nanocrystals.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
CURRENT DRUG METABOLISM
·
2024
·Vol. 25
·期 5
·317-329
·
IF 2.1
Xiaocui Li,Qi Liang,Caiyan Wang,Huawei Qiu,Tingting Lin,Wentao Li,Rong Zhang,Zhongqiu Liu,Lijun Zhu
BackgroundYunaconitine (YAC) is a hidden toxin that greatly threatens the life safety of patients who are prescribed herbal medicines containing Aconitum species; however, its underlying mechanism remains unclear.ObjectiveThe objective of this study is to elucidate the functions of P-glycoprotein (P-gp) in regulating the efficacy, toxicity, and pharmacokinetics of YAC.MethodsThe efflux function of P-gp on YAC was explored by using Caco-2 monolayers in combination with the P-gp inhibitor verapamil. The impact of P-gp on regulating the analgesic and anti-inflammatory effects, acute toxicity, tissue distribution, and pharmacokinetics of YAC was determined via male Mdr1a gene knocked-out mice and wild-type FVB mice.ResultsThe presence of verapamil significantly decreased the efflux ratio of YAC from 20.41 to 1.07 in Caco-2 monolayers (P < 0.05). Moreover, oral administration of 0.07 and 0.14 mg/kg YAC resulted in a notable decrease in writhing times in Mdr1a-/- mice by 23.53% and 49.27%, respectively, compared to wild-type FVB mice (P < 0.05). Additionally, the deficiency of P-gp remarkably decreased the half-lethal dose (LD50) of YAC from 2.13 to 0.24 mg/kg (P < 0.05). Moreover, the concentrations of YAC in the tissues of Mdr1a-/- mice were statistically higher than those in wild-type FVB mice (P < 0.05). Particularly, the brain accumulation of YAC in Mdr1a-/- mice significantly increased by 12- and 19-fold, respectively, after oral administration for 30 and 120 min, when compared to wild-type FVB mice (P < 0.05). There were no significant differences in the pharmacokinetic characteristics of YAC between Mdr1a-/- and wild-type FVB mice.ConclusionYAC is a sensitive substrate of P-gp. The absence of P-gp enhances the analgesic effect and toxicity of YAC by upregulating its brain accumulation. Co-administration with a P-gp inhibitor may lead to severe YAC poisoning.
研究领域:
药理学
·
毒理学
·
中药学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）