Water as a Reactant: DABCO-Catalyzed Hydration of Activated Alkynes for the Synthesis of Divinyl Ethers.

A practical and efficient addition of water to readily available activated alkynes delivering divinyl ethers is reported. The reaction proceeds with full atom economy in a very straightforward experimental procedure. Additionally, of all the tertiary amines studied to catalyze the reaction, the best and most efficient is clearly DABCO (1,4-diazabicyclo[2.

Amoebicidal effect of synthetic indoles against spp.: a study of cell death.

Organic and synthetic chemistry plays a crucial role in drug discovery fields. Moreover, chemical modifications of available molecules to enhance their efficacy, selectivity and safety have been considered as an attractive approach for the development of new bioactive agents. Indoles, a versatile group of natural heterocyclic compounds, have been widely used in pharmaceutical industry due to their broad spectrum of activities including antimicrobial, antitumoral and anti-inflammatory among others.

Dynamic Hydroxyl-Yne Reaction with Phenols.

Dynamic Covalent Chemistry (DCvC) has gained increasing importance in supramolecular chemistry and materials science. Herein we prove the dynamic nature of the exchange between phenols and vinyl ethers. Exchange is fast at room temperature and under mild conditions.

Short and Modular Synthesis of Substituted 2-Aminopyrroles.

We herein describe a simple and metal-free domino methodology to synthesize 2-aminopyrroles from alkynyl vinyl hydrazides. The domino reaction involves a novel propargylic 3,4-diaza-Cope rearrangement and a tandem isomerization/5-exo-dig N-cyclization reaction. By using this approach, a number of 2-aminopyrroles with diverse substituents have been prepared.

Design, Synthesis and Characterization of HIV-1 CA-Targeting Small Molecules: Conformational Restriction of PF74.

Small molecules targeting the PF74 binding site of the HIV-1 capsid protein (CA) confer potent and mechanistically unique antiviral activities. Structural modifications of PF74 could further the understanding of ligand binding modes, diversify ligand chemical classes, and allow identification of new variants with balanced antiviral activity and metabolic stability. In the current work, we designed and synthesized three series of PF74-like analogs featuring conformational constraints at the aniline terminus or the phenylalanine carboxamide moiety, and characterized them using a biophysical thermal shift assay (TSA), cell-based antiviral and cytotoxicity assays, and in vitro metabolic stability assays in human and mouse liver microsomes.

A General and Scalable Synthesis of Polysubstituted Indoles.

A consecutive 2-step synthesis of -unprotected polysubstituted indoles bearing an electron-withdrawing group at the C-3 position from readily available nitroarenes is reported. The protocol is based on the [3,3]-sigmatropic rearrangement of -oxyenamines generated by the DABCO-catalyzed reaction of -arylhydroxylamines and conjugated terminal alkynes, and delivers indoles endowed with a wide array of substitution patterns and topologies.

Recent Advances in the Synthesis of 2-Pyrans.

In this review, we discuss the nature of the different physicochemical factors affecting the valence isomerism between 2-pyrans (2HPs) and 1-oxatrienes, and we describe the most versatile synthetic methods reported in recent literature to access to 2HPs, with the only exception of 2HPs fused to aromatic rings (i.e., 2-chromenes), which are not included in this review.

Synthesis and Utility of 2,2-Dimethyl-2 H-pyrans: Dienes for Sequential Diels-Alder/Retro-Diels-Alder Reactions.

The practical use of 2,2-dimethyl-2 H-pyrans as electron-rich dienes in sequential Diels-Alder/retro-Diels-Alder (DA/rDA) domino processes to generate aromatic platforms has been demonstrated. Different polysubstituted alkyl 2-naphthoates have been synthesized by the DA/rDA reaction of benzynes and 2,2-dimethyl-2 H-pyrans. The use of other activated alkynes allows the access of substituted alkyl benzoate derivatives.

Nonspecific electrocardiographic abnormalities are associated with increased length of stay and adverse cardiac outcomes in prehospital chest pain.

Background: Nonspecific ST-T repolarization (NST) abnormalities alter the ST-segment for reasons often unrelated to acute myocardial ischemia, which could contribute to misdiagnosis or inappropriate treatment. We sought to define the prevalence of NST patterns in patients with chest pain and evaluate how such patterns correlate with the eventual etiology of chest pain and course of hospitalization.

Methods: This was a prospective observational study that included consecutive prehospital chest pain patients from three tertiary care hospitals in the U.