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The catalytic efficiency of a bifunctional chiral thiourea derived from L-proline was evaluated in the asymmetric direct vinylogous Michael reaction of α,α-dicyanoolefins to β-nitrostyrenes with an electron- releasing or electron-withdrawing substituent in various positions. The corresponding adducts were isolated in good yields, with excellent diastereo- (>99%) and enantioselectivity (up to 95%). The Michael adducts were further functionalized to achieve the synthesis of polycyclic fused pyrrolidines with three contiguous stereocenters in good enantioselectivities. [ABSTRACT FROM AUTHOR]