Green, rapid, and highly efficient syntheses of
<i>α</i>
,
<i>α′</i>
‐bis[(aryl or allyl)idene]cycloalkanones and 2‐[(aryl or allyl)idene]‐1‐indanones as potentially biologic compounds via solvent‐free microwave‐assisted Claisen–Schmidt condensation catalyzed by MoCl
<sub>5</sub>
作者:Reza Bakhshi、Behzad Zeynizadeh、Hossein Mousavi
DOI:10.1002/jccs.201900081
日期:2020.4
A new, green, and highly efficient protocol for the expeditious preparation of some α,α′‐bis[(aryl or allyl)idene]cycloalkanones and 2‐[(aryl or allyl)idene]‐1‐indanones via a simple microwave‐assisted Claisen–Schmidt condensation reaction catalyzed by MoCl5 was successfully developed. Outstanding features of the current methodology include the use of solvent‐free conditions, simple operation, use of
Abstract Tunable organometallic Lewisacidcatalysts were developed by combining salicylic acid (H2-Sal) with benzoic acid (H-Ben), 4-fluorobenzoic acid (H-BenF) and 3-thiophenic acid (H-Th), as coligands for mixed bis-carboxylate titanocene complexes. Three air-stable complexes [Cp2Ti(η1-HSal)(η1-Ben)] (1), [Cp2Ti(η1-HSal)(η1-BenF)] (2) and [Cp2Ti[η1-HSal][(η1-Th)] (3) were prepared in high yields
摘要 以水杨酸 (H2-Sal) 与苯甲酸 (H-Ben)、4-氟苯甲酸 (H-BenF) 和 3-噻吩酸 (H-Th) 作为混合配体,开发了可调有机金属路易斯酸催化剂。双羧酸二茂钛络合物。三种空气稳定配合物 [Cp2Ti(η1-HSal)(η1-Ben)] (1), [Cp2Ti(η1-HSal)(η1-BenF)] (2) 和 [Cp2Ti[η1-HSal][(η1- Th)] (3) 通过水杨酸二茂钛螯合物与羧酸盐配体的反应以高产率制备。通过物理化学和光谱方法充分表征了混合的双羧酸二茂钛配合物。单晶 X 射线衍射研究揭示了 Ti-O(H-Sal) 键距分别为 1.972(3)、1.9245(18) 和 1.912(5) Å,而键距涉及1、2 和 3 的配体为 1.908(3) Å (Ti-OBen)、1.9296(19) Å (Ti-OBenF) 和 1。分别为 945(5) Å (
Functionalized curcumin analogs as potent modulators of the Wnt/β-catenin signaling pathway
作者:Pay-Chin Leow、Priti Bahety、Choon Pei Boon、Chong Yew Lee、Kheng Lin Tan、Tianming Yang、Pui-Lai Rachel Ee
DOI:10.1016/j.ejmech.2013.10.073
日期:2014.1
Osteosarcoma is a primary bone malignancy with aggressive metastatic potential and poor prognosis rates. In our earlier work we have investigated the therapeutic potential of curcumin as an anti-invasive agent in osteosarcoma by its ability to regulate the Wnt/beta-catenin signaling pathway. However, the clinical use of curcumin is limited owing to its low potency and poor pharmacokinetic profile. In this study, an attempt was made to achieve more potent Wnt inhibitory activity in osteosarcoma cells by carrying out synthetic chemical modifications of curcumin. We synthesized a total of five series consisting of 43 curcumin analogs and screened in HEK293T cells for inhibition of beta-catenin transcriptional activity. Six promising analogs, which were 6.5- to 60-fold more potent than curcumin in inhibiting Wnt activity, were further assessed for their anti-invasive activity and Wnt inhibitory mechanisms. Western blot analysis showed disruption of beta-catenin protein nuclear translocation following treatment with analogs 2f, 3c and 4f. Using transwell assays, we also found that these compounds were more potent than la (curcumin) in impeding the invasion of osteosarcoma cells, possibly through suppressing MMP-9 activity. Structure-activity-relationship studies revealed that Wnt inhibitory effects could be enhanced by shortening and restraining the flexibility of the 7-carbon linker moiety connecting the terminal aromatic rings of curcumin and substituting both rings with appropriate substituents. Our results demonstrate that the synthesized curcumin analogs are more potent Wnt inhibitors in osteosarcoma cell lines as compared to parental curcumin and are good lead compounds for further development. Future in vivo tests with these compounds will define their therapeutic potentials as promising drug candidates for clinical treatment of osteosarcoma. (C) 2013 Elsevier Masson SAS. All rights reserved.
A RhCl(PPh3)3/BF3·OEt2 co-promoted direct C–C cross-coupling of alcohols at β-position with aldehydes
A novel RhCl(PPh3)(3)/BF3 center dot OEt2 co-promoted direct C-C cross-coupling of primary and secondary alcohols at beta-position with aldehyde was developed. This reaction could provide an efficient synthesis of a series of alpha, beta-unsaturated aldehydes and diarylidene ketones, just from simple and easily available alcohols and aldehydes. (C) 2009 Elsevier Ltd. All rights reserved.
Cremlyn, Richard J.; Frearson, Martin J.; Graham, Stephen, Phosphorus, Sulfur and Silicon and the Related Elements, 1995, vol. 107, # 1-4, p. 205 - 218
作者:Cremlyn, Richard J.、Frearson, Martin J.、Graham, Stephen