52999-15-2

Yndiamides (bis-N-substituted alkynes) are valuable precursors to azacycles. Here we report a cycloisomerization/1,2-sulfonyl migration of alkynyl-yndiamides to form tetrahydropyrrolopyrroles, unprecedented heterocyclic scaffolds that are relevant to medicinal chemistry. This functional group tolerant transformation can be achieved using Au(I) catalysis that proceeds at ambient temperature, and a thermally promoted process. The utility of the products is demonstrated by a range of reactions to functionalize the fused pyrrole core.

Palladium supported magnetic nanoparticle (Pd@Fe3O4/AMOCAA) was easily prepared in the presence of Scrophularia striata extract and fully characterized by FT-IR, SEM, VSM, TEM, TGA, XRD and EDAX. It was successfully employed as an easily separable and reusable effective heterogeneous catalyst classical Suzuki and Sonogashira cross-coupling reaction. Sustainability of the methodology was reserved by easy recovery of the catalyst using an external magnet and reusing it for 7 times without appreciable loss of its catalytic activity.

Heterocyclic compounds of Formula (I) and pharmaceutically acceptable salt thereof are disclosed. The use of such heterocyclic compounds and pharmaceutically acceptable salt thereof for the treatment of cancers, and more particularly cancers sensitive to mitochondrial activity inhibition and increased reactive oxygen species (ROS) levels, is also disclosed. Such cancers include acute myeloid leukemia (AML), preferably AML characterized by certain features, such as high level of expression of one or more Homeobox (HOX)-network genes, high and/or low expression of specific genes, the presence of one or more cytogenetic or molecular risk factors such as intermediate cytogenetic risk, Normal Karyotype (A/K), mutated NPM1, mutated CEBPA, mutated FLT3, mutated DNMT3A, mutated TET2, mutated IDH1, mutated IDH2, mutated RUNX1, mutated WT1, mutated SRSF2, intermediate cytogenetic risk with abnormal karyotype (intern(abnK)), trisomy 8 (+8) and/or abnormal chromosome (5/7), and/or a high leukemic stem cell (LSC) frequency.

A robust and general protocol for a sustainable copper-free Sonogashira cross coupling under micellar aqueous reaction conditions with high turnover was developed. By using the commercially available catalyst CataCXium A Pd G3 and THF as co-solvent, vario

A simple method for the synthesis of 3-thiosubstituted pyrroles from homopropargylic amines and thiosulfonates via a tandem sulfenylation/cyclization has been developed. The thiosulfonates are used both as substrates and oxidants in this transformation. This procedure exhibits good functional group tolerance and a series of 3-thiosubstituted pyrrole derivatives was obtained in moderate to good yields. (Figure presented.).

A Cu-catalyzed method for the synthesis of 3,3′-bipyrroles from homopropargylic amines through tandem aerobic oxidative cyclization involving the formation of C-C bond has been developed. The features of this reaction are a small number of Cu catalysis and simple starting substrates. Moreover, this procedure exhibits good functional group tolerance and a series of 3,3′-bipyrroles derivatives are obtained in moderate to good yields.

An efficient catalytic asymmetric cyclization/inverse-electron-demand hetero-Diels-Alder cascade reaction of β,γ-unsaturated α-ketoesters with alkyl amides or alcohols were accomplished. The process was based on the utilization bimetallic catalyst system with achiral gold(I) catalyst and chiral N,N′-dioxide/Ni(II) catalyst, delivering a variety of fused bicyclic N,O-acetals or O,O-acetals in up to 99% yield and 99% ee with >19:1 dr under mild reaction conditions. Based on the control experiments and previous studies, a possible reaction pathway of bimetallic relay catalysis cascade reactions was presented. (Figure presented.).

The invention discloses application of polymer microspheres to Raman detection. Methacrylate/amide polymer monomers or styrene polymer monomers containing alkynyl, cyano, azido or a carbon-deuterium bond group are prepared into the polymer microspheres with the particle diameter from a nanometer grade to a micron grade through an emulsion polymerization or dispersion polymerization method; the polymer microspheres have a remarkable Raman signal under the condition of no metal sensitization structure; and a Raman characteristic peak signal is located in a Raman quiet zone (1800cm to 2800cm) in a living organism and can be used as a marker for biological imaging.

An intermolecular condensation of alkynols and terminal alkynes is reported. Using IPrAuNTf2, an efficient Au-catalyzed cyclization-alkynylation strategy furnishes (2-arylalkynyl) cyclic ethers in moderate to excellent yields (up to 94%). This strategy is extended to the synthesis of functionalized 2,3-dihydrooxepines via the sequential Au-catalyzed ring expansion of the cyclic ether substrates.

Blocking the 2-C-methyl-d-erythrithol-4-phosphate pathway for isoprenoid biosynthesis offers new ways to inhibit the growth of Plasmodium spp. Fosmidomycin [(3-(N-hydroxyformamido)propyl)phosphonic acid, 1] and its acetyl homologue FR-900098 [(3-(N-hydroxyacetamido)propyl)phosphonic acid, 2] potently inhibit 1-deoxy-d-xylulose-5-phosphate reductoisomerase (Dxr), a key enzyme in this biosynthetic pathway. Arylpropyl substituents were introduced at the β-position of the hydroxamate analogue of 2 to study changes in lipophilicity, as well as electronic and steric properties. The potency of several new compounds on the P. falciparum enzyme approaches that of 1 and 2. Activities against the enzyme and parasite correlate well, supporting the mode of action. Seven X-ray structures show that all of the new arylpropyl substituents displace a key tryptophan residue of the active-site flap, which had made favorable interactions with 1 and 2. Plasticity of the flap allows substituents to be accommodated in many ways; in most cases, the flap is largely disordered. Compounds can be separated into two classes based on whether the substituent on the aromatic ring is at the meta or para position. Generally, meta-substituted compounds are better inhibitors, and in both classes, smaller size is linked to better potency.

The combination of triazole/gold (TA-Au) and Cu(OTf)2is identified as the optimal catalytic system for promoting intramolecular hydroboration for the synthesis of a six-membered cyclic amine–borane. Excellent yields (up to 95 %) and regioselectivities (5-exo vs. 6-endo) were achieved through catalyst control and sequential dilution. Good functional-group tolerance was attained, thus allowing the preparation of highly functionalized cyclic amine–borane substrates, which could not be achieved using other methods. Deuterium-labeling studies support the involvement of a hydride addition to a gold-activated alkyne with subsequent C?B bond formation.

Glycine, as a kind of commercially available and inexpensive ligand, is used to prepare an air-stable and water-soluble catalyst used in Sonogashira reaction in our study. In the presence of 1% [PdCl2(NH2CH2COOH)2/su

Rapid and versatile access to (Z)-trisubstituted olefins 2 and their cyclization into 4-aryl-2H-chromenes 1 starting fromarylalkynes 3 is described. In a one-pot fashion, alkynes 3 were first hydrated, then transformed into N-tosylhydrazones, and finally

We recently described an iterative synthesis of oligo-vinyl ethers, followed by a radical cascade to provide a family of hexahydro-2H-furo[3,4-b] pyrans. Our results for the radical cascade were consistent with either a direct 6-endo-trig addition of a vinyl radical onto the first vinyl ether function or an initial 5-exo-trig addition, followed by rearrangement to the more stable anomeric radical intermediate. In this report, we describe our further mechanistic studies aimed at distinguishing between these two possibilities and conclude that the 5-exo/3-exo/retro-3-exo pathway is dominant.

A first example of organo-N-heterocyclic carbene (NHC) catalyzed click-type fast 1,3-dipolar cycloaddition of nitrile oxides with alkynes was developed for the regioselective synthesis of 3,5-di- and 3,4,5-trisubstituted isoxazoles. Triethylamine (Et

A simple, highly efficient and phosphine-free protocol for the Sonogashira coupling of aryl iodides with terminal alkynes has been developed using Pd 2(dba)3 (dba=dibenzylideneacetone) as the catalyst under aqueous, copper-free and a

A heterogeneous catalyst, nanosized MCM-41-Pd, was used to catalyze the Sonogashira coupling of aryl and heteroaryl halides with terminal alkynes in the presence of CuI and triphenylphosphine. The coupling products were obtained in high yields using low Pd loadings to 0.01 mol%, and the nanosized MCM-41-Pd catalyst was recovered by centrifugation of the reaction solution and re-used in further runs without significant loss of reactivity.

The use of neopentylphosphine ligands in the palladium-catalyzed Suzuki, Sonogashira, Heck, and Hartwig-Buchwald couplings of aryl bromides and chlorides are reported. Di-tert-butylneopentylphosphine (DTBNpP) provided highly active catalysts for the coupling of aryl bromides at mild temperatures. Trineopentylphosphine, an air-stable trialkylphosphine, gave inactive catalysts at room temperature, but showed good activity in the H-B amination of aryl chlorides at elevated temperatures.

(Chemical Equation Presented) A variety of substituted benzotriazoles have been prepared by the [3 + 2] cycloaddition of azides to benzynes. The reaction scope is quite general, affording a rapid and easy entry to substituted, functionalized benzotriazoles under mild conditions.

A variety of aryl iodides were coupled with aromatic and aliphatic terminal alkynes to give the corresponding 1,2-disubstituted aromatic alkynes in good yields by using only 0.4 mol % of the heterogeneous 10% Pd/C as the catalyst without a ligand, copper

3-(Di-tert-butylphosphonium)propane sulfonate (DTB-PPS) and 3-(diadamantylphosphonium)propane sulfonate (DAPPS) are air-stable pre-ligands for aqueous-phase palladium-catalyzed cross-coupling reactions. Both DTBPPS and DAPPS were found to give active catalysts for the Sonogashira coupling of aryl bromides at room temperature and 4-chloroanisole at 80 °C. These ligands also gave effective catalysts for the aqueous-phase Suzuki coupling of aryl bromides at room temperature.

The integrin αvβ3 is expressed in a number of cell types and is thought to play a major role in several pathological conditions. Various small molecules that inhibit the integrin have been shown to suppress tumor growth and retinal a

(Chemical Equation Presented) An efficient and reusable Cu 2O/PPh3/TBAB (n-Bu4NBr) system for the cross-coupling reactions of aryl and heteroaryl halides with terminal alkynes has been developed. Four types of Cu2O, including bulky Cu 2O, cubic Cu2O nanoparticles, octahedral Cu2O nanoparticles, and spherical Cu2O nanoparticles, were examined, and the octahedral Cu2O nanoparticles were found to be the most effective catalyst for the reaction. In the presence of the octahedral Cu2O nanoparticles, PPh3, and TBAB, a variety of aryl and heteroaryl halides were reacted with alkynes including alkynols smoothly in moderate to good yields. Noteworthy is that the Cu2O/ PPh3/TBAB system can be recovered and reused several times without loss of any activities.

The tandem cycloisomerization-hydroalkoxylation of various homopropargylic alcohols in the presence of an alcohol and a dual catalyst system, consisting of a gold precatalyst and a Bronsted acid, provides an efficient route to tetrahydrofuranyl ethers und

Cross-coupling reactions of terminal alkynes with organic halides catalyzed by palladium(0) or palladium(0)/Cu(I) take place in the presence of several activators, such as silver(I) oxide, tetrabutylammonium fluoride (TBAF), and tetrabutylammonium hydroxi

This invention relates to processes for the preparation of cyclopropyl compounds of Formula: (I) wherein: x is an integer selected from the group consisting of 0, 1 and 2; R and R are independently selected from the group consisting of H, C1-C6 alkyl, and halo; and R, R, R, R and R are independently selected from the group consisting of H, C1-C6 alkyl, C1-C6 alkoxy, and halo.

An easy copper-, ligand and amine-free Sonogashira coupling reaction catalyzed by commercially available palladium on carbon with air at low catalyst loading (0.2 mol% Pd) has been developed. Aryl iodides coupled with aromatic alkynes gave good to excelle

The present invention relates to a class of compounds represented by the Formula I or a pharmaceutically acceptable salt thereof, pharmaceutical compositions comprising compounds of the Formula I, and methods of selectively inhibiting or antagonizing the αvβ3 and/or αvβ5 integrin.

Coupling reaction of terminal alkynes catalyzed by Pd/Cu with several organic electrophiles is shown to proceed by use of tetrabutylammonium fluoride (TBAF) or tetrabutylammonium hydroxide (TBAOH) as an activator. Treatment of 1-octyne and 4-methoxy-iodob

The enantiospecific Nicholas reaction, i.e. cobalt-promoted Friedel-Crafts reaction leading from chiral reactant to chiral product, was demonstrated for the first time. - Key Words: Nicholas reaction; enantiospecific; cobalt-stabilized carborations; 1-ethynyltetralin

A novel regio- and stereoselective synthesis of the dienamide piperovatine is described.This method does not suffer from problems associated with doublebond migration.

The four 4-substituted-homopropargyl tosylates and triflates 6b-e (R=phenyl, p-tolyl, anisyl, and cyclopropyl) have been synthesized and solvolyzed under various conditions, as have 2-cyclopropyl-1-cyclobutenyl triflate (11-OTf) and nonaflate (11-ONf).In addition, the solvolyses of pent-3-yn-1-yl tosylate (6a-OTs, R=methyl) and triflate (prepared previously) are reported.The ratios of C-3 ring to C-4 ring 3 ring/C4ring)> products are recorded for the reactions in various solvents.As expected, ring closure (kΔ) increases and solvent displacement (kS, SN2) decreases with decreasing nucleophilicity of solvent.Temperature effects are noted for the sovolyses of tosylates 6a-e in 100percent TFE buffered with Na2CO3 in which kΔ increases with increasing temperature.The result is explained by decomposition of the intimate ion pair with temperature, whereupon elimination to the enyne becomes smaller and ring closure (kΔ) increases at the expense of elimination.The possibility of intervention of nonclassical vinyl cations is discussed, as are other mechanistic implications.