NEW JOURNAL OF CHEMISTRY
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2019
·Vol. 43
·期 43
·16881-16888
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IF 3.069
Tenghe Zhang,Xinlu Li,Hang Song,Shun Yao
In order to both investigate the universality of ionic liquid-based catalytic systems for synthesis of triterpene saponins and explore their effective application methods together with the catalytic behaviors of ionic liquids in related reactions by comparison between different initiators, oleanolic acid and ursolic acid were selected to establish a catalytic system for glycosylation in this study as typical representatives of pentacyclic triterpene sapogenins. As a result, it was found that the system of [C4mim][OTf] + TMSOTf in the reactions between the glycosyl receptors and donors showed obvious catalytic effects; also, the system was stable and could be recycled. The functions of IL include solvent, cocatalyst and stabilizer, simultaneously; thus, the current catalytic system is greener, simpler and more efficient. The reaction time was short, and only β-type products were obtained. This study offers a reference for developing a new glucoside synthesis technology and provides sufficient preliminary exploration and basic data for further large-scale applications.
研究领域:
有机化学
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药物化学
✓ 已验证
产品关联
DOI
高影响因子
ULTRASONICS SONOCHEMISTRY
·
2024
·
IF 8.7
Jie Li,Shichun Li,Shiliang Huang,Jinjiang Xu,Qilong Yan,Shaohua Jin,Yu Liu
Low sensitivity octahydro-1,3,4,7-tetranitro-1,3,5,7-tetrazocine (HMX) has garnered significant attention from researchers due to its reduced shock sensitivity. However, the crystallization process poses challenges due to the high solidity and viscosity of the metastable α phase. Despite efforts to address this with additional energy sources like ultrasonic irradiation, prolonged exposure duration often results in small particle sizes, hindering the production of HMX with a consistent particle size distribution, thus limiting its applicability. To overcome these challenges, a method combining ultrasonic irradiation and trace H + additive was proposed and investigated for their impact on the polymorphic transformation of HMX. The H + additive was found to modify barriers, thus there was a lack of competitive driving force for the nucleation or growth of the metastable α form, thereby shortening the transformation pathway and duration. Moreover, the H + additive significantly accelerated the nucleation rate of the β form (67.7 orders of magnitude faster with 0.10 wt ‰ H + ) and the growth rate of β form HMX (5.8 orders of magnitude faster with 0.10 wt ‰ H + ). While H + additive alone was insufficient to induce spontaneous nucleation of the β form, combining it with short-duration ultrasonic irradiation further promoted β nucleation and shortened the polymorphic transformation duration (almost 20 orders of magnitude shorter). This rational approach led to effective control of the transformation process. The resulting low sensitivity HMX crystals exhibited varying mean sizes ranging from 20 to 340 μm, with purity exceeding 99.6 %, an apparent density greater than 1.8994 g/cm 3 , and few internal defects, fully meeting the requirements of low-sensitivity HMX, thus significantly expanding its potential applications. Our study sheds light on the mechanisms governing HMX polymorphic transformation in the presence of additives and ultrasonic irradiation, offering guidance for the rational control of this complex transformation.
研究领域:
材料科学
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化学工程
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炸药科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CRYSTENGCOMM
·
2024
·
IF 2.6
Yujing Ren,Xiubin Hou,Ying Zhang,Jingyan Hao,Juan Gao,Xinbing Song,Yurong Ma
Anhydrous guanine (AG) crystals are widely applied in organisms due to their excellent optical properties. However, the influence of biomolecules on the biomineralization process of guanine crystals in organisms remains unexplored. In this study, mixed proteins from the silver film of carp fish scales were extracted and were used as a model system to elucidate the effect of biomolecules on the guanine crystallization for the first time. The mixed proteins were enriched with amino acids such as Asp, Glu, Leu and Lys. Elongated hexagonal microplates of α-form AG (α-AG) mixed with a small amount of β-form AG (β-AG) mainly exposing (100) plane were obtained in the presence of the mixed proteins under mild condition while irregular particles were formed in the absence of proteins, indicating that the extracted mixed proteins have a strong influence on the formation of AG microplates exposing (100) plane. It is found that the proteins not only adsorb on the surface but also occluded into the AG crystals by using confocal laser scanning microscopy analysis. We also find that guanine analogues have profound synergetic effects on the morphology and polymorphs of guanine in the in-vitro synthetic system. The obtained α-AG exhibit superior optical properties such as high reflectivity, strong depolarization and pearlescent luster. This in-vitro synthesis work shows clearly the strong influence of biomolecules for the biomineralization process of guanine crystals in the organisms.
研究领域:
生物矿化
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材料科学
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生物化学
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光学
✓ 已验证
产品关联
DOI
高影响因子
PHYTOMEDICINE
·
2023
·
IF 7.9
Yi Cai,Shisheng Jiang,Chaoming Huang,Ao Shen,Xuan Zhang,Wanling Yang,Yichuan Xiao,Shuhan Gao,Rong Du,Guodong Zheng,Tingdong Yan,Chunpeng (Craig) Wan
Background The conserved sirtuin protein sirtuin 3 (SIRT3) is a vital protective protein for cardiac hypertrophy. Inhibition of SIRT3 accelerated the development of heart hypertrophy. On the other hand, myocardial hypertrophy was prevented by overexpressing SIRT3. SIRT3 has been proposed as a potential therapeutic target for managing or averting heart hypertrophy. Baicalin, a flavonoid extracted from the Scutellaria baicalensis plant, has anti-cardiovascular properties, including protection against cardiac hypertrophy. However, the molecular mechanism of the anti-hypertrophic effect of baicalin is not well known. Purpose In this study, we aim to investigate the effect of baicalin on cardiac hypertrophy and explored its underlying molecular mechanisms. Study-design/methods Abdominal aortic constriction (AAC)-induced mouse cardiac hypertrophy and angiotensin II (Ang II)-induced cardiomyocyte hypertrophy models were established. After baicalin treatment, cardiac hypertrophy was monitored by detecting the expression of hypertrophic genes and cell surface area. Echocardiogram was performed to check the heart function in vivo . Moreover, the protein expression of the SIRT3-dependent pathway was detected by Western blotting. Results In this work, we demonstrated that baicalin might suppress the cell surface area and the expression of the Ang II -induced myosin heavy chain β (β-MHC), brain natriuretic polypeptide (BNP), and atrial natriuretic factor (ANF). Additionally, it reduced the AAC rats' hypertrophic impact. We also found that baicalin prevents cardiac hypertrophy by regulating SIRT3/LKB1/AMPK signaling pathway. Moreover, we showed that baicalin upregulated the SIRT3 protein expression by inhibiting proteasome and by the activation of 20 S proteasome subunit beta type-5 (PSMB5). Conclusion These results offer the first proof that baicalin inhibits cardiac hypertrophy due to its effect on the SIRT3-dependent signaling pathway, indicating its potential for treating cardiac hypertrophy and heart failure. The present study provides a preliminary experimental basis for the clinical application of baicalin and baicalin-like compounds.
研究领域:
心脏病学
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药理学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）