| Summary: | The AgOAc-catalysed reaction of 3-nitro-2-phenyl-2<i>H</i>-chromenes with stabilized azomethine ylides generated from the imines based on methyl glycinate and arylaldehydes leads to a mixture of <i>endo</i> and <i>endo</i>’ isomers of the corresponding chromeno[3,4-<i>c</i>]pyrrolidines in a ratio of 2.0–2.3:1 in 85–93% total yields as a result of a Michael addition/Mannich reaction sequence. In a similar reaction involving 2-trifluoromethyl-3-nitro-2<i>H</i>-chromenes, only <i>endo</i> chromeno[3,4-<i>c</i>]pyrrolidines are formed in 85–94% yields. 3-Nitro-2-(trichloromethyl)-2<i>H</i>-chromenes under the same conditions react with these azomethine ylides to give the corresponding Michael adducts as individual <i>anti</i>-isomers with the <i>cis</i>,<i>trans</i>-configuration of the chromane ring in 40–67% yields. Some 4-CF<sub>3</sub>-substituted chromano[3,4-<i>c</i>]pyrrolidines exhibited high cytotoxic activity against HeLa human cervical carcinoma cells.
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