BINAP-CuH-catalysed enantioselective allylation using alkoxyallenes to access 1,2-,-diols.

Herein, we present an economical method for highly enantioselective and diastereoselective Cu-BINAP-catalysed reductive coupling of alkoxyallenes with a range of electronically and structurally diverse ketones to afford 1,2-,-diols, using PMHS as the hydride source. This reductive coupling has also been efficiently employed in the enantioselective desymmetrization of prochiral cyclic ketones harboring quaternary centres, in high yields with exclusive diastereoselectivity. Density Functional Theory (DFT) calculations are used to elucidate that the reaction is facilitated by a kinetically favourable "open" -enolate copper-alkoxyallene conformer, occurring at a lower Gibbs free energy barrier (by 3.

Design and application of intramolecular arylogous nitroaldol condensation to access 2-aryl-benzofuran and -indole derivatives and formal synthesis of saprisartan.

This study presents the design and application of intramolecular arylogous nitroaldol (Henry) condensation. A transition metal-free, base-mediated reaction of -heteroatom-substituted aryl aldehydes/ketones and 2-nitrobenzyl (pseudo)halides has been developed to access a wide range of 2-(2-nitroaryl)benzofuran/2-(2-nitroaryl)indole derivatives in high yields. The reaction appears to proceed through -/-benzylation and intramolecular arylogous nitroaldol condensation.

Severity prediction markers in dengue: a prospective cohort study using machine learning approach.

Background: Dengue virus causes illnesses with or without warning indicators for severe complications. There are no clear prognostic signs linked to the disease outcomes.

Methods: Clinical and laboratory parameters among 102 adult including 17 severe dengue (SD), 33 with warning and 52 without warning signs during early and critical phases were analysed by statistical and machine learning (ML) models.

NHC-Catalyzed Umpolung Driven Intramolecular Cyclizations for the Generation of 3,4-Cycloheptanone Annulated Tetracyclic Indole Derivatives.

In this Letter, we disclose the development and exploitation of umpolung reactivity of N-heterocyclic carbene (NHC) organocatalysts in generating tetracyclic indole derivatives with the introduction of a cycloheptane ring forming event. The NHC-catalyzed intramolecular vinylogous Stetter, Stetter, benzoin, and formal cross-dehydrogenative coupling transformations have been executed, enabling the construction of 3,4-cycloheptannulated indole derivatives in good to excellent yields. The developed protocols utilize an inexpensive catalyst and feature operational simplicity, atom economy, gram-scale syntheses, and postsynthetic availability.

Total Synthesis of an Immunosuppressive C Macrocyclic Terpenoid Produced by Terpene Synthase (2).

Macrocyclic natural products, particularly those with no functionalities except unsaturation, are recognized for their therapeutic potential but are notoriously challenging to synthesize. In this study, we report the first total synthesis of an unconventional 18-membered, C macrocyclic terpenoid, which has demonstrated substantial immunosuppressive activity. This synthesis was achieved through strategic modifications and innovative reaction engineering, utilizing α-terpineol and geraniol as starting materials, highlighting a novel approach in macrocyclic terpenoid synthesis.

Visible-Light-Promoted Iron(II)/Lewis Base Catalysis for the Alkylation of Morita-Baylis-Hillman Acetates Using Carboxylic Acids.

A novel photoinduced Fe(OTf)/2,4,6-collidine-catalyzed alkylation of Morita-Baylis-Hillman (MBH) acetates using carboxylic acids in a regio- and stereoselective manner is reported. This method demonstrates a broad scope, encompassing various carboxylic acids and MBH acetates, including drugs and bioactive molecules, to synthesize densely functionalized cinnamates and acrylates. The reactions are performed in the green solvent dimethyl carbonate under oxidant-free conditions.

Acid-Mediated Intramolecular Cyclizations of (-Aryl)-acetylenic Sulfonamides: Synthesis of Fused and Spirocyclic Sultams.

Herein, we report acid-mediated divergent annulations of (-aryl)-alkynyl sulfonamides. The substituent at the position of the -aryl group determines two diverse reaction paths, leading to the selective assembly of benzo-fused sultams and spirocyclic sultams. This strategy provides a series of benzo/spiro-sultams with wide functional group compatibility and good to excellent yields under mild reaction conditions.

Ag(I)-catalyzed diastereoselective oxidative cyclopropanation of prochiral alkyne-tethered 1,3-dicarbonitriles.

Herein, we developed a highly diastereoselective silver-catalyzed intramolecular cyclopropanation of prochiral alkyne-tethered 1,3-dicarbonitriles using perchloric acid as an effective oxidizing agent. This method facilitates the construction of densely functionalized complex [6.6.

Increased shedding of PECAM-1 associated with elevated serum MMP-14 levels as new blood indicators of dengue disease manifestation.

Objectives: Host factors that regulate plasma leakage during severe dengue (SD) are under investigation. While PECAM-1 and MMP-14 have been reported to regulate vascular integrity, their role in dengue pathogenesis remains unexplored. This study aims to assess the association of soluble PECAM-1 and MMP-14 with dengue severity symptoms.

Cascade Oxypalladation/1,3-Palladium Shift to Access Cyclopentene-Fused Isocoumarins.

Fused isocoumarins are frequently found in several natural products and pharmaceuticals. Herein, a cascade annulation of 2-alkynylbenzoate-tethered cyclic 1,3-diones via sequential -oxypalladation, carbonyl insertion, 1,3-Pd shift, and β-hydride elimination is reported. This method provides efficient access to highly diastereoselective tetracyclic cyclopentene-fused isocoumarins containing two contiguous quaternary stereocenters.

Nickel-Catalyzed Alkene Isomerization to Access Bench-Stable Enamines and Their [3 + 2] Annulation.

Enamines are difficult to prepare on the bench due to their instability, which results in side reactions, decompositions, poor yields, etc. Herein, we developed a simple and effective method for making bench-stable enamines using a very low amount of nickel catalyst loading. The deuterium exchange, competitive reaction, and radical clock experiment have all been found to favor the ionic mechanism of this alkene isomerization.

Understanding COVID-19 outcome: Exploring the prognostic value of soluble biomarkers indicative of endothelial impairment.

Host proteins released by the activated endothelial cells during SARS-CoV-2 infection are implicated to be involved in coagulation and endothelial dysfunction. However, the underlying mechanism that governs the vascular dysfunction and disease severity in COVID-19 remains obscure. The study evaluated the serum levels of Bradykinin, Kallikrein, SERPIN A, and IL-18 in COVID-19 (N-42 with 20 moderate and 22 severe) patients compared to healthy controls (HC: N-10) using ELISA at the day of admission (DOA) and day 7 post-admission.

Glucosyltriazole amphiphile treatment attenuates breast cancer by modulating the AMPK signaling.

Breast cancer is the second most frequent cancer among women. Out of various subtypes, triple-negative breast cancers (TNBCs) account for 15% of breast cancers and exhibit more aggressive characteristics as well as a worse prognosis due to their proclivity for metastatic progression and limited therapeutic strategies. It has been demonstrated that AMP-activated protein kinase (AMPK) has context-specific protumorigenic implications in breast cancer cells.

Access to N-Fused Quinazolinones by Radical-Promoted Cascade Annulations of Alkenyl -Cyanamides with Aromatic Aldehydes.

A cascade radical cyclization of alkenyl -cyanamides with aromatic aldehydes has been achieved for an expeditious synthesis of keto-methylated dihydropyrrolo-quinazolinones. Benzoyl radicals, generated from aryl aldehydes in the presence of di--butyl peroxide (DTBP), promoted the domino annulations leading to distinctive functionalized quinazolinones in good yields. In addition, the robustness of the present protocol is validated by employing heterocyclic and natural product-based aldehydes.

Purification of Waste-Generated Biogas Mixtures Using Covalent Organic Framework's High CO Selectivity.

Development of crystalline porous materials for selective CO adsorption and storage is in high demand to boost the carbon capture and storage (CCS) technology. In this regard, we have developed a β-keto enamine-based covalent organic framework () via the Schiff base polycondensation technique. The as-synthesized exhibited excellent thermal and chemical stability along with a very high surface area (1258 m g) and a high CO adsorption capacity (3.

Deoxyfluorinated amidation and esterification of carboxylic acid by pyridinesulfonyl fluoride.

Amide bond synthesis is one of the most used reactions in medicinal chemistry. We report an amide bond formation reaction through deoxyfluorinated carboxylic acids under mild conditions using 2-pyridinesulfonyl fluoride. The reaction procedure has been used in a one-pot synthesis of amides and esters generation of acyl fluoride.

Organocatalytic enantioselective desymmetrization of enal-tethered cyclohexane-1,3-diones.

Organocatalytic asymmetric desymmetrization of prochiral cyclohexane-1,3-diones has been demonstrated through the merging of iminium and enamine activation. The tandem annulation reaction proceeds through a sequential oxa-Michael addition/intramolecular aldol reaction/[1,3]-amino oxetane rearrangement pathway. Mechanistic study using an O-water experiment suggests oxetane rearrangement instead of direct dehydration.

Modulating cultivation regimes of Messastrum gracile SVMIICT7 for biomass productivity integrated with resource recovery via hydrothermal liquefaction.

The present study was designed to assess Messastrum gracile SVMIICT7 potential in treating dairy wastewater (autoclaved (ADWW) and raw (DWW)) with relation to nutrient removal, in-vivo Chl-a-based biomass, and bio-oil synthesis. Chlorophyll a fluorescence kinetics revealed improved photochemical efficiency (0.639, Fv/Fm) in M.

NHC-Catalyzed Formal [4 + 2] Annulation of -Formyl-Tethered Michael Acceptors and Ynones to Access Highly Functionalized Naphthalene Derivatives.

Herein we demonstrate a novel organocatalytic method to access multifunctionalized naphthalenes an NHC-catalyzed reaction of ynones and -formyl-tethered Michael acceptors. The presented method proceeds through an intermolecular Stetter reaction-cyclization-aromatization cascade and represents a rare example of organocatalytic benzannulation for the synthesis of substituted arenes by using ynone as a two-carbon synthon. The current method has broad substrate scope; postsynthetic transformations and gram-scale syntheses highlight the practicality of the displayed methodology.

One-Pot Synthesis of -Fused Benzimidazo-β-carbolines through Sequential Propargylation/-Cycloisomerization Approach.

The first sequential acid-catalyzed propargylation/base-mediated -cycloisomerization between indolyl-benzimidazoles and propargylic alcohols is described. This protocol enables the one-pot construction of -fused benzimidazo-β-carbolines in good yields. The synthetic utility of this approach is demonstrated by the assembly of an -helicene and also by a gram-scale reaction.

Carbene-Catalyzed Tandem Imine Umpolung-Intramolecular Aza-Conjugate Addition-Oxidation to Access -Substituted Isoindolinones.

Herein, we have described a novel N-heterocyclic carbene (NHC)-catalyzed synthesis of -substituted isoindolinone acetates. The presented transformation proceeds through NHC-catalyzed tandem imine umpolung-intramolecular aza-Michael addition followed by oxidation, while molecular oxygen in air acts as a sole oxidant. Atom efficiency, operational simplicity, large-scale syntheses, and mild reaction conditions are the salient features of this method.

Biorefinery-centric ethanol and oleochemical production employing Yarrowia lipolytica and Pichia farinosa.

The research examined the capabilities of Yarrowia lipolytica (YL) and Pichia farinosa (PF) in converting sugars to ethanol and oleochemicals. Lipid, ethanol, protein yield and gene-expressions were analysed at different substrate concentrations (3 to 30 g/L) with glucose, food waste, and fermentation-effluent. Optimal results were obtained at 20 g/L using both synthetic carbon with 4.

Comprehensive Study on Solomonamides: Total Synthesis, Stereochemical Revision, and SAR Studies toward Identification of Simplified Lead.

Solomonamides, a pair of macrocyclic peptide natural products originating from marine sources, have garnered significant attention within the synthetic community owing to their marked anti-inflammatory efficacy and intricate molecular architectures. In this paper, we present a very detailed investigation into solomonamides, including the challenges associated with the total synthesis, the evolution of our synthetic strategies, structural reassignment, synthesis of all possible stereoisomeric macrocycles, biological assessment, structure-activity relationship (SAR) studies, etc. Within the ambit of this total synthesis, diverse strategies for macrocyclization were rigorously explored, encompassing the Friedel-Crafts acylation, cyclization involving the aniline NH moiety, macrolactamization utilizing Gly-NH, and Heck macrocyclization methodologies.