119703-89-8Relevant academic research and scientific papers
Enantioselective bromocyclization of allylic amides catalyzed by BINAP derivatives
Kawato, Yuji,Kubota, Akino,Ono, Hiromi,Egami, Hiromichi,Hamashima, Yoshitaka
, p. 1244 - 1247 (2015/03/14)
A highly enantioselective bromocyclization of allylic amides with N-bromosuccinimide (NBS) was developed with DTBM-BINAP as a catalyst, affording chiral oxazolines with a tetrasubstituted carbon center in high yield with up to 99% ee. By utilizing the bro
Solvent-dependent enantiodivergence in the chlorocyclization of unsaturated carbamates
Garzan, Atefeh,Jaganathan, Arvind,Salehi Marzijarani, Nastaran,Yousefi, Roozbeh,Whitehead, Daniel C.,Jackson, James E.,Borhan, Babak
, p. 9015 - 9021 (2013/07/26)
A remarkable solvent-controlled enantiodivergence is seen in the hydroquinidine 1,4-phthalazinediyl diether ((DHQD)2PHAL)-catalyzed chlorocyclization of unsaturated carbamates. Eyring plot analyses of this previously unreported reaction are used to probe and compare the R- and S-selective pathways. In the CHCl3/hexanes solvent system, the pro-R process shows a surprising increase in selectivity with increasing temperature. These studies point to a strongly solvent-dependent entropy-enthalpy balance between the pro-R and pro-S pathways. Two solvents, two enantiomers: Enantiodivergent hydroquinidine 1,4-phthalazinediyl diether ((DHQD) 2PHAL)-catalyzed chlorocyclization of unsaturated carbamates, controlled solely by the choice of solvent, yields oxazolidinones in high enantioselectivity (see scheme; DCDMH=1,3-dichloro-5,5-dimethyl hydantoin). The origin of the observed enantiodivergence is traced back to a solvent-selected entropy-enthalpy balance between pro-R and pro-S pathways that dictates the course of the reaction. Copyright
Characterization of a series of 3-amino-2-phenylpropene derivatives as novel bovine chromaffin vesicular monoamine transporter inhibitors
Perera, Rohan P.,Wimalasena, D. Shyamali,Wimalasena, Kandatege
, p. 2599 - 2605 (2007/10/03)
A series of 3-amino-2-phenylpropene (APP) derivatives have been synthesized and characterized as novel competitive inhibitors, with Ki values in the μM range, for the bovine chromaffin granule membrane monoamine transporter(s) (bVMAT). Although, these inhibitors are structurally similar to the bVMAT substrate tyramine, none of them were measurably transported into the granule. Structure - activity studies have revealed that, while the 3′- or 4′-OH groups on the aromatic ring enhance the inhibition potency, Me or OMe groups in these positions reduce the inhibition potency. Halogen substitution on the 4′-position of the aromatic ring causes gradual increase of the inhibition potency parallel to the electron donor ability of the halogen. Substituents on the NH2 as well as on the 3-position of the alkyl chain reduce the inhibition potency. Comparative structure - activity analyses of APP derivatives with tyramine and the neurotoxin 1-methyl-4-phenylpyridinium suggest that the flexibility of the side chain and the relative orientation of the NH2 group may be critical for the efficient transport of the substrate through the bVMAT. Comparable bVMAT affinities of these inhibitors to that of DA and other pharmacologically active amines suggest that they are suitable for the structure activity and mechanistic studies of monoamine transporters and may also be useful in modeling the mechanism of action of amphetamine-related derivatives.
