RESUMO
A novel tandem oxidative Ritter reaction/hydration/aldol condensation of α-arylketones with substituted propiolonitriles has been developed. This protocol conveniently affords a wide range of functionalized 3-acyl-3-pyrrolin-2-ones through the efficient construction of four chemical bonds, a C-N bond, a CâC bond, and two CâO bonds, and the formation of one ring bearing an aza-quaternary center, which is ascribed to the strategical introduction of functionalized nitriles to this transformation. A reaction mechanism was proposed based on some control experiments.
RESUMO
Objectives: This study aimed to analyze the influencing factors of hospitalization cost of hypertensive patients in TCM (traditional Chinese medicine, TCM) hospitals, which can provide a scientific basis for hospitals to control the hospitalization cost of hypertension. Methods: In this study, 3,595 hospitalized patients with a primary diagnosis of tertiary hypertension in Tianshui City Hospital of TCM, Gansu Province, China, from January 2017 to June 2022, were used as research subjects. Using univariate analysis to identify the relevant variables of hospitalization cost, followed by incorporating the statistically significant variables of univariate analysis as independent variables in multiple linear regression analysis, and establishing the path model based on the results of the multiple linear regression finally, to explore the factors influencing hospitalization cost comprehensively. Results: The results showed that hospitalization cost of hypertension patients were mainly influenced by length of stay, age, admission pathways, payment methods of medical insurance, and visit times, with length of stay being the most critical factor. Conclusion: The Chinese government should actively exert the characteristics and advantages of TCM in the treatment of chronic diseases such as hypertension, consistently optimize the treatment plans of TCM, effectively reduce the length of stay and steadily improve the health literacy level of patients, to alleviate the illnesses pain and reduce the economic burden of patients.
Assuntos
Hospitalização , Hipertensão , Medicina Tradicional Chinesa , Humanos , Feminino , Hipertensão/economia , Masculino , Pessoa de Meia-Idade , Medicina Tradicional Chinesa/economia , Medicina Tradicional Chinesa/estatística & dados numéricos , Hospitalização/economia , Hospitalização/estatística & dados numéricos , China , Idoso , Tempo de Internação/estatística & dados numéricos , Tempo de Internação/economia , Adulto , Custos Hospitalares/estatística & dados numéricosRESUMO
The first enantioselective total syntheses of six natural and two proposed meroterpenoids isolated from Psoralea corylifolia have been achieved in 7-9 steps from 2-methylcyclohexanone. The current synthetic approaches feature a high level of synthetic flexibility, stereodivergent fashion and short synthetic route, thereby providing a potential platform for the preparation of numerous this-type meroterpenoids and their pseudo-natural products.
RESUMO
A novel thio-Ritter-type reaction of alkyl bromides, nitriles, and hydrogen sulfide has been explored, providing a straightforward approach toward functionally important thioamides. This transformation features a broad substrate scope, operational simplicity, use of available feedstock chemicals, and late-stage functionalizations of bioactive molecules. The reaction mechanism is also proposed.
Assuntos
Sulfeto de Hidrogênio , Tioamidas , Brometos , Estrutura Molecular , Nitrilas/química , Tioamidas/químicaRESUMO
A general γ-C(sp2)-H iodination method directed by an aliphatic keto group has been developed under transition-metal-free conditions for the first time, generating iodoarenes in good to excellent yields with excellent site selectivity. This protocol features a wide range of aryl-substituted ketones, short reaction times, mild reaction conditions, and scalable synthetic procedures. A possible reaction mechanism was also proposed based on several control experiments.
RESUMO
A p-toluenesulfonic acid catalyzed fluorination of α-branched ketones for the construction of fluorinated quaternary carbon centers has been developed, featuring a broad substrate scope, environmentally benign reaction conditions, and operational simplicity.
RESUMO
It has been reported that the cooperative binding of calcium ions indicated a local conformational change of the human cytosolic phospholipase A2 (cPLA2) C2 domain (Nalefski et al., (1997) Biochemistry 36, 12011-12018). However its structural evidence is less known (Malmberg et al., (2003) Biochemistry 42, 13227-13240). In this letter, life-time decay and fluorescence quenching techniques were employed to compare the calcium-induced conformational changes. The life-time decay parameters and fluorescence quenching constant changes were small between the apo- and holo-C2 domains when tryptophan residue was excited at 295 nm. In contrast, the quenching constant change was large, from 0.52 M(-1) for the apo-C2 to 8.8 M(-1) for the holo-C2 domain, when tyrosine residues were excited at 284 nm. Our results provide new information on amino acid side chain orientation change at calcium binding loop 3, which is necessary for Ca2+ binding regulated membrane targeting of human cytosolic phospholipase A2.