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As a base structural unit, 1,4-dihydropyridines (DHPs) containing benzosultams widely exist in bioactive molecules and drugs. These compounds are generally synthesized by organic-base catalyzed methods that require specifically functionalized substrates or harsh conditions. Herein, a [3+3] annulation reaction of cyclic N-sulfonyl ketimine with various substituted isatylidene malononitrile or benzylidene malononitriles was documented. This biocatalytic strategy provides a green route for synthesis of 1,4-DHPs containing benzosultams, with good functional groups compatibility and yields. Under optimal conditions, lipase leads to the formation of 1,4-DHPs containing benzosultams in up to 87% yield. [ABSTRACT FROM AUTHOR]

The development of non-natural enzymatic catalysis is important for multicomponent tandem organic transformations. However, the delicate acting environments of biological enzymes still present some challenges in the synthesis of spirooxindole skeleton via enzymatic catalysis. To address these issues, a lipase-catalyzed method was developed for the synthesis of spirooxindole frameworks. Using easily available isatins, cycloketones, and malononitriles as substrates, mild reaction conditions, and a reasonable reaction time, moderate to good yields (67–92%) and excellent functional group tolerance were accomplished via this protocol. The related mechanism explanation is also speculated in this paper. [ABSTRACT FROM AUTHOR]

• Hemin is used as a highly selective catalyst for the direct aminoselenation and oxyselenation of alkenes. • High yields of the desired products were obtained with good functional group tolerance. • A new biomimetic method to synthesize β-alkoxyl/ hydroxy selenides and β-amido selenides was established. The highly selective hemin-catalyzed three-component aminoselenation and oxyselenation of alkenes has been developed using various nucleophiles. Remarkably, the use of acetonitrile as a green and attractive solvent in an organic reaction, the use of simple TBHP (tert -butyl hydroperoxide) as a mild oxidant, the use of a biodegradable catalyst, simple workup procedure, and good functional group tolerance (39 examples) are added features to this biomimetic method for the preparation of various difunctionalized organoselenium derivatives. These characteristics demonstrate the scalability of the current strategy for academic research and industrial applications. [Display omitted] [ABSTRACT FROM AUTHOR]