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• Burning velocities of LCV syngas-air at elevated pressures and temperatures. • A modified power-law correlation for burning velocity is proposed. • Effect of simultaneous change in temperature and pressure on burning velocity analysed. Laminar burning velocities of low-calorific value syngas-air mixtures are measured at elevated temperature and pressure conditions using externally heated diverging channel method. The technique facilitates direct measurement of laminar burning velocities simultaneously at elevated pressures and temperatures. The mixture burning velocities are observed to increase with mixture enthalpy at elevated temperatures and decrease with an increase in the mixture pressure. The measurements are carried out for a mixture temperature range of 300–650 K and up to 5 bar pressure. Based on these measurements a new relation for the variation of laminar burning velocity with pressure and temperature is proposed. The power-exponents of temperature and pressure were expressed as linear functions of pressure and temperature ratios, respectively. The comparison of the measured burning velocities with the best performing kinetic schemes (FFCM-1 and Aramco 3) revealed that a significant deviation in the predictions is observed, when a simultaneous increase in pressure and temperature are considered. [ABSTRACT FROM AUTHOR]

[Display omitted] This study describes the development of a new and rapid synthesis procedure for performing the aryl and benzyl substituted 2-methylquinazolin-4(3H)-one ring cyclization reaction. We utilized a continuous-flow microfluidic reactor for the production of quinazolinone derivatives of a humanin peptide mimetic screening hit in a facile manner, offering a cleaner reaction profile, high yield, and quick scalability. Our results show the power of flow chemistry to this reaction and can be of general utility for synthesizing quinazolinone-containing intermediates and final products of industrial importance in a continuous and safe manner. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Development of microfluidic reaction scheme for synthesis of fused indoline ring systems by flow chemistry. • Green chemistry approach with clean reaction profile, good yields and quick scalability. • Continuous-flow in a microfluidic reactor for interrupted Fischer indolization reaction. • General utility to rapidly produce indoline scaffolds and intermediates of industrial importance. Abstract This study describes our development of a microfluidic reaction scheme for the synthesis of fused indoline ring systems found in several bioactive compounds. We have utilized a continuous-flow microfluidic reactor for the reaction of hydrazines with latent aldehydes through the interrupted Fischer indolization reaction to form fused indoline and azaindoline products. We have identified optimal conditions and evaluated the scope of this microfluidic reaction using various hydrazine and latent aldehyde surrogates. This green chemistry approach can be of general utility to rapidly produce indoline scaffolds and intermediates in a continuous manner. [ABSTRACT FROM AUTHOR]

This study describes our development of a novel and efficient procedure for C O bond formation under mild conditions, for coupling heteroaryl chlorides with phenols or primary aliphatic alcohols. We utilized a continuous-flow microfluidic reactor for C O bond formation in electron-deficient pyrimidines and pyridines in a much more facile manner with a cleaner reaction profile, high yield, quick scalability, and without the need for the transition metal catalyst. This approach can be of general utility to make C O bond containing intermediates of industrial importance in a continuous and safe manner. [ABSTRACT FROM AUTHOR]

Abstract: The structure activity relationship of the prime region of conformationally restricted hydroxyethylamine (HEA) BACE inhibitors is described. Variation of the P1′ region provided selectivity over Cat-D with a series of 2,2-dioxo-isothiochromanes and optimization of the P2′ substituent of chromane–HEA(s) with polar substituents provided improvements in the compound’s in vitro permeability. Significant potency gains were observed with small aliphatic substituents such as methyl, n-propyl, and cyclopropyl when placed at the C-2 position of the chromane. [Copyright &y& Elsevier]

Abstract: The structure–activity relationship of the prime region of hydroxyethylamine BACE inhibitors is described. Variation in the aryl linker region with 5- and 6-membered heterocycles provided compounds such as 33 with improved permeability and reduced P-gp liability compared to benzyl amine analog 1. [Copyright &y& Elsevier]

Abstract: Herein we describe further evolution of hydroxyethylamine inhibitors of BACE-1 with enhanced permeability characteristics necessary for CNS penetration. Variation at the P2′ position of the inhibitor with more polar substituents led to compounds 19 and 32, which retained the potency of more lipophilic analog 1 but with much higher observed passive permeability in MDCK cellular assay. [ABSTRACT FROM AUTHOR]

Abstract: Using structure-guided design, hydroxyethylamine BACE-1 inhibitors were optimized to nanomolar Aβ cellular inhibition with selectivity against cathepsin-D. X-ray crystallography illuminated the S1′ residues critical to this effort, which culminated in compounds 56 and 57 that exhibited potency and selectivity but poor permeability and high P-gp efflux. [Copyright &y& Elsevier]