C3sc50811k 3427..3431
نویسندگان
چکیده
The enantioselective bromocyclization of allenes is accomplished through the use of a chiral dinuclear gold complex and/or chiral phosphate anions in the presence of an N-bromolactam as an electrophilic bromine source. This method provides access to heterocyclic vinyl bromides with an allylic stereocenter in excellent yield and enantioselectivity. These enantioenriched vinyl bromides may serve as a handle for further derivatization via cross-coupling reactions.
منابع مشابه
Ergonomic analysis of safety signs: a focus of informational and cultural ergonomics.
This paper presents the results of a research carried out in the states of Pernambuco and Rio Grande do Sul, Brazil about differences and similarities in the graphic representation of safety signs at factories of food, steel, shoes and construction/ building industries, together with their workers' opinions on the security signs. The overall results show differences in the sign structure across...
متن کاملbcl-2 inhibits wild-type p53-triggered apoptosis but not G1 cell cycle arrest and transactivation of WAF1 and bax.
We have earlier shown that wild-type (wt) p53 expressed from a temperature-sensitive construct (ts p53) triggers apoptosis in the v-myc retrovirus-induced, p53-negative T-cell lymphoma line J3D (Y. Wang et al., Cell Growth & Differ., 4: 467-473, 1993). We also found that constitutive bcl-2 expression inhibits wt p53-triggered apoptosis in these cells (Y. Wang et al., Oncogene, 8: 3427-3431, 199...
متن کاملPMN J1838–3427: A new gravitationally lensed quasar
We report the discovery of a new double-image quasar that was found during a search for gravitational lenses in the southern sky. Radio source PMN J1838–3427 is composed of two flat-spectrum components, separated by 1 in VLA and VLBA images, with matching spectral indices. An HST/WFPC2 image reveals the lens galaxy between the components. The background object is a z = 2.78 quasar, but the reds...
متن کاملKaryotypes found in the population declared at increased risk of Down syndrome following maternal serum screening.
Of the 65 328 pregnancies of South Australian mothers screened by the South Australian Maternal Serum Antenatal Screening (SAMSAS) Programme between 1 January 1991 and 31 December 1997, 3431 (5.25%) were declared at increased risk of fetal Down syndrome. Fetal or neonatal karyotype was determined in 2737/3431 (79.8%) of these pregnancies, including 16 with early fetal loss. Interrogation of the...
متن کامل