± 88 to 964 ± 76 dyn-sec-cm-5 (mean ± SEM) (p < 0.001). As a result, pulmonary artery wedge pressure decreased from 18 ± 2 to 15 ± 2 mm Hg (p < 0.025), cardiac index increased from 2.5 ± 0.1 to 3.7 ± 0.2 I/min/m2 (p < 0.001) and stroke volume index increased from 30 ± 2 to 39 ± 2 mI/m' (p < 0.001). The effects of hydralazine on exercise hemodynamics were evaluated in 12 patients. Before treatme...

The development of intermolecular [2 + 2]-cycloaddition of α-iodo-unsaturated ketones in the presence of diisobutylaluminum hydride (Dibal-H) is reported to produce various trispirocyclic derivatives containing a cyclobutane ring. This sequential lactonization/[2 + 2]-cycloaddition proceeds in high regioselectivity under mild conditions.

BACKGROUND This is a supplemental report on tests of the long-term effects of universal preventive interventions conducted during middle school on 17-21-year-olds' prescription drug misuse. DESIGN/SETTING/PARTICIPANTS Two randomized controlled prevention trials were conducted in public schools in the rural midwestern United States. Study 1 began in 1993, with 667 6th-graders; follow-ups with ...

A series of 6-alkenyl-3-phenylcyclohex-2-enones has been synthesised and the structures of the products obtained from them on irradiation have been determined. The 6-propenyl compounds afforded a tricyclic 'parallel' [2 + 2] cycloaddition product and a bicyclic enone resulting from hydrogen abstraction in the biradical intermediate. The 6-butenyl and 6-pentenyl analogues gave 'crossed' cycloadd...

synthesis of some new monocyclic β-lactams containing a quaternary carbon center via a [2+2]cycloaddition reaction is described. the reaction of achiral diphenyl ketene with chiral aldimines derivedfrom chiral 2, 3, 4, 6-tetra-o-acetyl-β-d-galactopyranosylamine, 2, 3, 4, 6-tetra-o-acetyl-β-dglucopyranosylamine and different benzaldehydes resulted in the formation of β-lactams as singlediastereo...

This paper describes the synthesis of three closely related families of mannopyranoside-containing dendrimers for the purpose of studying subtle structural parameters involved in the measurements of multivalent carbohydrate-protein binding interactions. Toward this goal, two trimers 5 and 9, three 9-mers 12, 17, 21, and one 27-mer 23, varying by the number of atoms separating the anomeric and t...

Abstract Metal-catalyzed [2+2+2] cycloaddition is a powerful tool that allows rapid construction of functionalized 6-membered carbo- and heterocycles in single step through an atom-economical process with high functional group tolerance. The reaction usually regio- chemoselective although selectivity issues can still be challenging for intermolecular reactions involving the cross-[2+2+2] two or...