Oxidative amide synthesis and N-terminal alpha-amino group ligation of peptides in aqueous medium.

A new method for oxidative synthesis of amides from alkynes and amines in high yields (up to 96%) using [Mn(2,6-Cl2TPP)Cl] 1 as a catalyst and Oxone/H2O2 as an oxidant in aqueous medium has been developed. This method could be used for N-terminal alpha-amino group ligation of unprotected peptides with aryl, aliphatic, and internal alkynes under mild conditions.

Dioxiranes generated in situ from pyruvates and oxone as environmentally friendly oxidizing agents for disinfection.

Dioxiranes generated in situ from pyruvates (alpha-keto esters) and Oxone have been found to be environmentally friendly oxidizing agents for disinfection. These oxidizing agents were highly effective for destruction of various strains of bacteria, fungi, and bacterial endospores in a wide temperature range with exceptional stability. Notably, by using an aqueous solution of methyl pyruvate (1a) and Oxone/NaHCO3, complete destruction of bacteria such as Staphylococcus aureus and fungus Penicillium corylophilum was achieved within 5 min at 20 degrees C at neutral pH.

Comparison of an oxygen-powered flow-limited resuscitator to manual ventilation with an adult 1,000-mL self-inflating bag.

Background: Positive-pressure ventilation of patients with unprotected airways during cardiopulmonary resuscitation can cause gastric dilation.

Objective: Determine if there is a significant difference in volume delivered to lungs and stomach while using an adult 1,000-mL disposable bag-valve-mask (BVM) device and the oxygen-powered, flow-limited Oxylator EMX resuscitator.

Methods: We used a bench model to simulate a patient with an unprotected airway, consisting of an intubation manikin, lung analog, and simulated lower esophageal sphincter set at an opening pressure of 20 cm H2O.

Metalloporphyrin-catalyzed diastereoselective epoxidation of allyl-substituted alkenes.

By using [Mn(2,6-Cl(2)TPP)Cl] (1) as a catalyst and Oxone/H(2)O(2) as an oxidant, we have developed an efficient method for erythro-selective epoxidation of acyclic allyl-substituted alkenes, including allylic alcohols, amines, and esters. Up to 9:1 erythro selectivities for terminal allyllic alkenes could be achieved, which are significantly higher than that achieved using m-CPBA as an oxidant. In addition, the synthetic utilities of this epoxidation method were highlighted in stereoselective synthesis of key anti-HIV drug intermediates and epoxidation of glycals.

Highly diastereoselective epoxidation of allyl-substituted cycloalkenes catalyzed by metalloporphyrins.

Highly diastereoselective epoxidations of allyl-substituted cycloalkenes including allylic alcohols, esters, and amines using sterically bulky metalloporphyrins [Mn(TDCPP)Cl] (1) and [Ru(TDCPP)CO] (2) as catalysts have been achieved. The "1 + H(2)O(2)" and "2 + 2,6-Cl(2)pyNO" protocols afforded trans-epoxides selectively in good yields (up to 99%) with up to >99:1 trans-selectivity.

A cyclodextrin-modified ketoester for stereoselective epoxidation of alkenes.

A beta-cyclodextrin-modified ketoester 2 was prepared by covalent attachment of a reactive ketone moiety to beta-cyclodextrin. Treatment of 2 with Oxone as terminal oxidant would produce CD-substituted dioxirane, which can effect stereoselective alkene epoxidation. The 2-mediated (S)-alpha-terpineol epoxidations proceeded to give terpineol oxides in high yields, and the stereoselectivities (i.