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A multicomponent cascade cyclization reaction using aryl methyl ketones, aryl amines, and enaminamide reagents to construct 3‐hydroxy‐1H‐pyrrolo[3,4‐b]quinolin‐1‐one skeleton with good substrate compatibility (50 examples) has been reported. The one‐pot, metal‐free process formed two C−C bonds, two C−N bonds, and a tetrasubstituted carbon stereocenter containing a hydroxyl group. The reaction enabled modified transformation of drug molecules and derivatization of products. [ABSTRACT FROM AUTHOR]

An oxidant-controlled divergent synthesis of a pyrrolidone fused pyrimido[1,2-b]indazole skeleton was developed through selective cyclization of an in situ generated enone intermediate and 1H-indazol-3-amine. The one-pot, metal-free process formed three C–N bonds, one C–C bond, and a tetrasubstituted carbon stereocenter containing a hydroxyl group. This method not only allowed for the synthesis of over 60 new pyrrolidone fused pyrimido[1,2-b]indazole derivatives, but was also compatible with the transformation of complex active molecules and the derivation of target products. Significantly, product 4q exhibited aggregation-induced emission (AIE) characteristics without any further modification. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A [2 + 1 + 1 + 1] cyclization reaction has been developed for the synthesis of multisubstituted β‐pyrrolidinones from commercially available aryl methyl ketones, primary amines, and ethyl nitroacetate. In this I2–DMSO‐meditated process, the C—NO2 bond of ethyl nitroacetate is cleaved, affording a C1 synthon, and the formation of two C—C and two C—N bonds and a quaternary carbon center are constructed in one pot. This method has good substrate compatibility and permits the late‐stage modification of pharmaceutical compounds. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The conversion of CF3‐alkenes to gem‐difluoroalkenes using reductive cross‐coupling strategy has received much attention in recent years, however, the use of green and readily available reducing salt to mediate these reactions remains to be explored. In this work, a concise construction of gem‐difluoroalkenes, which requires neither a catalyst nor a metal reducing agent, was established. Rongalite, a safe and inexpensive industrial product, was employed as both a radical initiator and reductant. This procedure was compatible with both linear and cyclic diaryliodonium salts, enabling a wide variety of substrates (>70 examples). The utility of this approach was demonstrated through gram‐scale synthesis and efficient late‐stage functionalizations of anti‐inflammatory drugs. [ABSTRACT FROM AUTHOR]

A I2‐DMSO mediated approach to introduce −OCD3 into pyrroles in situ via multicomponent cascade cyclization reaction using methyl ketones, aniline, ethyl benzoylacetate and CD3OD as readily available substrates is reported. This process realizes introduction of −OCD3 into the Hantzsch pyrrole synthesis and synthesis of deuterated alkoxy‐substituted pyrroles with formation of one C−C bond, one C−O bond and two C−N bonds in one pot. Notably, this conversion has good substrate compatibility (62 examples) and eliminates of the need for anhydrous and anaerobic operation. [ABSTRACT FROM AUTHOR]

The aim of the test was to assess the nutrient composition and carbohydrate composition of more than 20 commonly used equine animal feeds in Southland. The results show that comparing the conventional composition of the 15 roughages measured. The CP content ranged from 3.31% to 19.43%, the EE content ranged from 1.23% to 2.94%, and the NDIP content ranged from 2.21% to 12.96%. Comparing the conventional composition of the five energy feeds, the CP content ranged from 5.66% to 15.63%, the EE content ranged from 1.60% to 4.08%, and the NDIP content ranged from 2.51% to 8.33%. Comparing the conventional composition of the four protein feeds, the CP content ranged from 23.75% to 46.32%, the EE content ranged from 1.26% to 15.99%, and the NDIP content ranged from 7.95% to 14.14%. Comparing 24 feedstuffs in terms of carbohydrate fraction, overall the CHO-H content of energy feeds was higher than protein feeds and most roughage, the CHO-FR content of energy feeds was higher than roughages and protein feeds, and the CHO-FS content of roughage was higher than that of energy feeds and higher than that of some protein feeds. Analysis of feeds according to the digestive characteristics of the equine genus, feeds with higher ratios on CHO-H and CHO-FR content are digested more quickly, thus the more rapidly digested of the roughage, energy and protein feeds are whole plant maize silage, dates and soya meal respectively. [ABSTRACT FROM AUTHOR]

The geometrical structures, stability and electronic properties of PtmIrn and PtmIrnNO (m + n = 8 − 1 0) clusters have been studied by using density functional theory (DFT). Simple cube evolution pattern is revealed for Ir 8 − 1 0 and Ir-rich clusters. The curve of the second-order energy difference of PtnIr (9 − n) clusters shows the evident even–odd oscillations, indicating that PtIr8, Pt3Ir6, Pt5Ir4 and Pt7Ir2 clusters are more stable than their neighbors. The minimum excess energies values are seen for Pt7Ir, PtIr8 and Pt2Ir8, which means that these clusters show the stronger mixing tendency. Analysis of magnetic properties shows that the total magnetic moment contributed from Ir and Pt atoms, and the magnetic moment mainly comes from localization of the d orbit electron. All ground-state structures show an adsorption of NO at the top site of the bare cluster via the N atom. In all of the alloy clusters, NO molecule prefers to be adsorbed near the Ir atom site. Fukui function is an accurate predictor of the reactivity on a specific adsorption site in Pt–Ir alloy clusters. [ABSTRACT FROM AUTHOR]