A model for computing image ow in image sequences containing a very wide range of instantaneous ows is proposed. This model integrates the spatio-temporal image derivatives from multiple temporal scales to provide both reliable and accurate instantaneous ow estimates. The integration employs robust regression and automatic scale weighting in a generalized brightness constancy framework. In addi...

Abstract One-pot two sequential [3 + 2] cycloadditions of azomethine ylides with different dipolarophiles for diastereoselective synthesis spirooxindole pyrrolizidines are introduced. This one-pot involving five components generates a highly condensed ring system bearing seven stereocenters diastereoselectively. The new method has high pot, atom, and step economy. Only equivalents water release...

an efficient one-pot three-component procedure for the synthesis of new chiral spiro oxindolopyrrolidines/pyrrolizidines with highly regio- and diastereo-enantio, selective from 1,3-dipolar cycloaddition of azomethine ylides and chiral menthol-drived trans-cinnamic are described. the mechanism of the reaction is discussed on basis of the assignment of the absolute configuration of one of the cy...

Structurally diverse highly functionalized flouro- and nitro - substituted spirooxindole-pyrrolidine heterocyclic hybrids have been achieved in good yields. The molecular structure of these spiroheterocyclic was elucidated by spectroscopic analysis further confirmed single crystal X-ray crystallographic studies density functional theory (DFT) calculations. Analysis packing for performed using H...

The CoI2(PPh3)2/Zn system effectively catalyzes the [2 + 2 + 2] ene-diyne cycloaddition of 1,6-heptadiynes with allenes in a highly regio- and chemoselective fashion to yield substituted benzene derivatives in good to excellent yields.

A new strategy for Rh(I)-catalyzed [2+2+2] cycloadditions of 1,6-diynes with potassium (Z)-(2-bromovinyl)trifluoroborate as the third two-atom unit has been realized, which provides a facile entry to polysubstituented benzene derivatives.

Hexa-substituted benzene derivatives show larger two-photon cross sections than the corresponding dipolar counterparts and the largest values of delta(max) = 2000 GM and delta(max)/MW = 2.25 GM g(-1) have been obtained with a compound having C[triple bond]C and C=C bonds in the conjugation bridge.