A copper-catalyzed asymmetric propargylic amination with a chiral ketimine P,N,N-ligand that proceeds via decarboxylation of propargyl carbamates has been developed. The reaction can be performed under the mild condition for a broad range of substrates, providing the corresponding propargylic amines in high yields and with up to 97% ee. This reaction represents a new and facile access to optica...

A highly efficient, simple and clean solvent-free protocol for the synthesis of polyhydroquinolines is described. The one-pot multi-component condensation reaction between arylaldehydes, dimedone (5,5-dimethylcyclohexane-1,3-dione), β-ketoesters and ammonium acetate in the presence of catalytic amount of (2.5 mol%) melamine trisulfonic acid (MTSA) as a recyclable, green and attractive sulfonic ...

In this work, SO3H-functionalizedphthalimide (SFP) as a SO3H-containing solid acid is prepared by the reaction of phthalimide with chlorosulfonic acid, and characterized by FT-IR, 1H and 13C NMR, Mass, TG, DTG, XRD and SEM. Then, it is utilized as a highly efficient, heterogeneous and green catalyst for the one-pot multi-component condensation of dime...

The combination of two or more unsaturated structural units to form cyclic organic compounds is commonly referred to as cycloaddition, and the combination of two unsaturated structural units that forms a six-membered ring is formally either a [5 + 1]-, [4 + 2]-, [2 + 2 + 2]-, or [3 + 3]-cycloaddition. Occurring as concerted or stepwise processes, cycloaddition reactions are among the most usefu...

ion agent (entry 4). Echavarren examined the intramolecular hydroarylation of alkynes with indoles, observing that the regioselectivity (formal 7-exo-dig vs 8-endo-dig) of the cyclization is highly dependent upon the catalytic Au source (Table 8). In the cyclization of 37, Ph3PAuCl/AgSbF6 resulted in little discrimination between the pathways leading to 38 and 39 (entry 4). Remarkably, AuCl and...

The neoclerodane diterpene salvinorin A (1) was isolated in 1982 from the rare mint SalVia diVinorum, indigenous to Oaxaca, Mexico.1 Recent efforts established salvinorin A as a potent and selective κ opioid receptor agonist, the only non-alkaloid psychoactive substance, and the most potent naturally occurring hallucinogen.2 As a result of its therapeutic potential, renewed isolation efforts ha...

Syntheses of the C1–C12 and C13–C28 oasomycin A subunits were described in the preceding Communication. Herein we describe the synthesis and assemblage of the C29–C46 portion of this polyketide natural product. According to the synthesis plan, the C29–C46 fragment targeted as aldehyde I is considered as one of the complex subgoals. Julia disconnection of the D olefin in I affords fragments II a...

Cross-dehydrogenative coupling reactions between -ketoesters and electron-rich arenes, such as indoles, proceed with high regiochemical fidelity with a range of -ketoesters and indoles. The mechanism of the reaction between a prototypical ketoester, ethyl 2-oxocyclopentanonecarboxylate and N-methylindole, has been studied experimentally by monitoring the temporal course of the reaction by 1 ...

Introduction Kinesin spindle protein (KSP), also known as Hs Eg5 has emerged as a promising target for a new generation antimitotic chemotherapeutic agents, it is a member of the kinesin superfamily of molecular motors that utilize the energy generated from the hydrolysis of ATP to transport vesicles, organelles, and microtubules [1-3]. Ispinesib has emerged as a potent KSP inhibitor with sub n...