Wenhai Li

Herein, we report a tandem nucleophilic cyclization-thermally triggered rearrangement/cleavage reaction using (E)-β-iodovinyl sulfones and acetohydroxamic acids as readily available substrates. With an oxaziridine serving as the pivotal intermediate, this synthetic protocol allows the temperature-dependent, divergent assembly of α-amido ketone and β-ketosulfone skeletons in an efficient manner. This approach broadens the synthetic utility of high-strain N,O-heterocyclic scaffolds and provides an efficient and versatile synthetic platform for accessing these two valuable functional molecular architectures.

A novel metal‐free (3 + 3) cyclization between pyridinium 1,4‐zwitterionic thiolates and 2‐bromoacetoanilide efficiently synthesizes functionalized 3,4‐dihydro‐2 H ‐1,4‐thiazines. This protocol offers remarkable substrate adaptability, easily prepared substrates and metal‐free catalysis. The findings highlight a practical metal‐free protocol for accessing 3,4‐dihydro‐2 H ‐1,4‐thiazines, circumventing limitations inherent to traditional metal catalysis and demonstrating the potential of 2‐bromoacetanilide in heterocyclic synthesis. Furthermore, biologically significant sulfone analogs are readily accessible via oxidation of the resulting thiazine products using m ‐CPBA.

A novel metal-free [3+2] cycloaddition strategy involving (E)-β-iodovinyl sulfones or bromoallylsulfones and pyridinium 1,4-zwitterionic thiolates for the efficient synthesis of sulfonylthiophenes is presented. This method exhibits good substrate tolerance, metal-free catalysis, and easily prepared bench-stable substrates. The findings highlight a practical metal-free protocol for accessing sulfonyl-substituted thiophenes with significant biological and chemical relevance, serving as an alternative to traditional metal catalysis and the oxidation of aryl/heteroaryl sulfides.

Herein, we describe an efficient, practical free-metal rapid access to active hexafluoroisopropyl benzoates from anthranils, HFIP, and α-halohydroxamates. Notably, this process includes anthranils undergone a distinct patten reaction. The protocol has good functional group tolerance and a broad substrate scope. Using simple and general method, we accomplished potential synthetic application of active ester.

A formal [3 + 2] cycloaddition reaction between the C and O terminals of azaoxyallyl cations formed in situ and 1,2-benzisoxazoles has been realized. This one-pot cycloaddition method provided an effective and practical pathway to synthesize oxazoline in good yields under mild conditions. The title products exhibited unique fluorescence properties.

The TGF-beta signaling pathway is important in the development and invasion of cancers. Int7G24A is an intronic variant of TGF-beta receptor type 1 and has been shown to be associated with the occurrence of some kinds of cancers. Nevertheless, the association of this polymorphism with osteosarcoma is unknown. In this study, we evaluated Int7G24A variant frequencies in osteosarcoma cases. The case–control study involved 168 osteosarcoma patients and 168 age- and gender-matched controls. The blood samples were obtained, and Int7G24A variant was determined by PCR amplification and DNA sequencing. The odds ratio (OR) and 95% confidence interval (95% CI) for the Int7G24A polymorphism were calculated using unconditional logistic regression adjusted for age and gender. Three analysis models, which are the dominant model, additive model and recessive model, were used to analyze the contribution of Int7G24A variant to osteosarcoma susceptibility. Heterozygotic and homozygotic Int7G24A variants were 33.93 and 6.55% in total 168 cases, while they were 28.57 and 2.98%, respectively, in total 168 controls. The ORs for homozygosity and heterozygosity of Int7G24A allele were 1.56 [95% CI, 0.98–1.83] and 2.89 [95% CI, 1.46–4.92] in additive model. The ORs of Int7G24A genotypes in dominant model and in recessive model were 1.75 [95% CI, 1.21–2.68] and 2.21 [95% CI, 1.34–4.72], respectively. There were significant increases in Int7G24A variants in osteosarcoma cases when compared to control in every three models. Further analysis showed that Int7G24A genotypes were not associated with gender and osteosarcoma location of the cases. However, Int7G24A was significantly increased in the cases less than 20 years old. Moreover, Int7G24A was significantly associated with increased distant metastasis of osteosarcoma. It is concluded that Int7G24A is a polymorphism of TGFBR1 that is associated with the susceptibility and distant metastasis of osteosarcoma.