367 research outputs found
Synthesis of thioesters through copper-catalyzed coupling of aldehydeswith thiols in water
Copper-catalyzed C–S bond formation between aldehydes and thiols in the presence of TBHP as an oxidant is described. Functional groups including chloro, trifluoromethyl, bromo, iodo, nitrile, ester and thiophene are all tolerated by the reaction conditions employed. This reaction is performed in water without the use of a surfactant. Both aryl and alkyl aldehydes couple suitably with aryl- and alkyl thiols, affording the corresponding thioesters in moderate to good yields
Manganese-Catalyzed Cross-Coupling of Thiols with Aryl Iodides
Here we report the manganesecatalyzedcoupling reaction of thiols witharyl iodides, giving the aryl thioethers ingood to excellent yields; the system showsgood functional group tolerance and enablesthe sterically demanding aryl iodides tocouple with thiols
A General Procedure for the Regioselective Synthesis of Aryl Thioethers and Aryl Selenides Through C–H Activation of Arenes
A general procedure for the synthesis of aryl thioethers and aryl selenides in one-pot through sequential iridium-catalyzed C–H borylation and copper-promoted C–S and C–Se bond formation is described. Functional groups including chloro, nitro, fluoro, trifluoromethyl, and nitrogen-containing heterocycles were all tolerated under the reaction conditions. Importantly, not only aryl thiols and selenides but also their alkyl analogs were suitable coupling partners, and the products were obtained in good yields with high meta regioselectivity
Metal-free sp(3) C-H functionalization: a novel approach for the syntheses of selenide ethers and thioesters from methyl arenes
A DTBP-promoted metal-free and solvent-free formation of C-Se and C-S bonds through sp(3) C-H functionalization of methyl arenes with diselenides and disulfides is described
Aesthetics of identity: Five views from comtemporary Taiwanese photography
“EstĂ©ticas de la Identidad” conmemora en Lima el DĂa Nacional de Taiwán que se celebra el dĂa 10 de octubre de 2021, junto a todos los amigos peruanos y a la querida colonia taiwanesa en el PerĂş, compartiendo algunas obras significativas de los cinco destacados y premiados fotĂłgrafos taiwaneses, que han capturado imágenes que nos muestran la identidad de Taiwán y su gran patrimonio cultural. Con seguridad encontraremos grandes similitudes con el PerĂş y su gran herencia cultural
Using the computer-based feedback (CBF) system to investigate the juniorphysicians’s and clinical-instructors perceptions for the benefits of general medicine clinical-instructors training program
Background: The purpose of this study is to examine the clinical-instructors and junior-physicians (residents and interns) perceptions for the general-medicine training program by using bi-directional interactive and self-assessments computer-based feedback (CBF) and paper-based multisource feedback assessment (PBMFA) systems for the efficiency and benefit evaluation.Methods: Between 2011 January to 2013 December, junior-physicians and their clinical-instructors in the same medical team were enrolled consecutively for monitoring the CBF scores gave by each other after each clinical course. A total of 321 residents, 298 interns and 110 clinical-instructors who participated in the core competency general-medicine training program in 6-months period were included in the study. The CBF and PBMFA evaluations are undergone paralleled to gather the suggested information in different levels of Kirkpatrick evolutional theory.Results: The results showed that lecturers, being 5-10 years as attending physicians, internal medicine sub-specialty clinical-instructors are most benefit from the general medicine training program. Accordingly, the CBF scores of junior-physicians was positively correlated with the times (> 3-times) of exposure to the medical teams that leaded by qualified clinical-instructors. Both clinical-instructors and junior-physicians have positive attitude to the value of the general-medicine training program. Interestingly, a good consistency was existed between residents CBF scores and PBMFA grades for their core-competency performance. Comparatively, the overall perception of clinical-instructors and junior-physicians for the general-medicine training was very positive.Conclusions: Clinical-instructors and junior-physicians had positive perception of CBF and PBMFA systems which could give us different information to improve and strength the further core-competency general-medicine training program by appropriate utilization
Anti-AIDS agents 86. Synthesis and anti-HIV evaluation of 2′,3′-seco-3′-nor DCP and DCK analogues
In a continuing study of novel anti-HIV agents with drug-like structures and properties, 30 1′-O-, 1′-S-, 4′-O- and 4′-substituted-2′,3′-seco-3′-nor DCP and DCK analogues (8–37) were designed and synthesized. All newly synthesized seco-compounds were screened against HIV-1NL4-3 and a multiple reverse transcriptase (RT) inhibitor-resistant (RTMDR) strain in the TZM-bl cell line, using seco-DCK (7) and 2-ethyl-DCP (4) as controls. Several compounds (14, 18, 19, 22–24, and 32) exhibited potent anti-HIV activity with EC50 values ranging from 0.93 to 1.93 μM and therapeutic index (TI) values ranging from 20 to 39. 1′-O-Isopropoxy-2′,3′-seco-3′-nor-DCP (12) showed the greatest potency among the newly synthesized compounds with EC50 values of 0.47 and 0.88 μM, and TI of 96 and 51, respectively, against HIV-1NL4-3 and RTMDR strains. The seco-compounds exhibited better chemical stability in acidic conditions compared with DCP and DCK compounds. Overall, the results suggested that seco-DCP analogues with simplified structures may be more favorable for development as novel anti-HIV candidates
- …