The biological activity of tetrakis(benzoxazine) calix[4]resorcinarenes and as a host for small molecules

New ten tetrakis(benzoxazine) calix[4]resorcinarenes modified by organic amine through Mannich reaction were obtained in this paper. Compounds 2  ~  11 were characterized by infrared spectroscopies, nuclear magnetic resonance spectroscopies. The structure of compounds 2 , 10 and 11 was characterized by single crystal X-ray diffraction. Compound 7 possesses a MIC value of 3.13 μg/mL against S. Aureus , demonstrating a favorable inhibitory effect, and a MIC value of 6.25 μg/mL against E. Coli , likewise showing a good inhibitory effect. The UV and 1 H NMR titration experiments were conducted to explore the host–guest chemistry between compound 10 and acetonitrile molecules, indicating that compound 10 exhibited encapsulation behavior towards acetonitrile molecules through hydrogen bonding interactions. Then Hirshfeld surface analysis showed that H⋅⋅⋅H, C − H⋅⋅⋅O, C − H⋅⋅⋅π, O − H⋅⋅⋅O played an important role in the crystal accumulation of compounds 2 , 10 and 11 .