Cover Pictures

In 1966, Prof. S. Swaminathan discovered the bicyclo[5.4.0] undecane skeletons, which are popularly known as Swaminathan ketones. These ketones are the potential synthons for many alkaloids. The cover picture depicts the Prof. Swaminathan and the importance of de novo catalytic asymmetric synthesis of chiral Swaminathan ketones.

Abstract: Besides numerous synthetic and biological applications, the catalytic construction of chiral Swaminathan ketones and their analogues possessing a bicyclo[5.4.0]undecane core structure has remained challenging for the scientific community for over four decades. Not more than five Swaminathan ketones (S. ketones) and their analogues are known in the literature to date. Herein, we report an unprecedented organocatalytic asymmetric desymmetrization strategy for the synthesis of chiral S. ketones and their analogues with excellent enantioselectivities from the corresponding 2-alkyl-2-(3-oxobutyl)-cycloheptane-1,3-diones via amine/acid-catalysed conformation-controlled intramolecular aldol condensation.

The Front Cover shows like the fungi, the organocatalytic multi-catalytic one-pot method also stands as a unique kingdom in the field of synthetic organic chemistry by simply making the impossible possible.

Abstract: Structurally complexcedrane scaffolds were synthesized in very good yields with high chemo-and diastereoselectivities in a sequential one-pot manner. A combination of intermolecular olefination, intramolecular Michael and Michael reactions or intermolecular olefination, intramolecular Michael and aldol reactions were used as the key steps from the readily available hydroxy-p-quinonebutanals and phosphoranes with catalytic amounts of quinine at ambient temperatures for a few hours.This is a unique one-pot combination of coupling and annulation routes for the green synthesis of a library of tricyclicpseudo-terpenoids(cedranescaffolds) with high selectivity and yields. Organocatalytic ring isomerization was highlighted through transforming one ring into another one by retro-cyclization. We have discussed thoroughly mechanistic aspects of these tandemcoupling/annulation and ring isomerization reactions based on control experiments and X-ray crystal structure analssis. by suing simple substarates abd conditions.

Lawsone is naturally obtained from Henna plant leaves (as shown in the cover image), which are responsible for the red-orange pigment properties. It is well known in the cosmetic industry as a natural coloring agent for hair, nails, and skin. Over the centuries, lawsone has been frequently used as a natural beauty product, but the pharmaceutical applications of lawsone and its analogs are still underexplored. To fulfill these shortcomings, we started utilizing lawsone as a synthon for a new class of cascade reactions to synthesize structurally complex molecules, which are analogues of biologically and pharmaceutically active molecules.

Abstract: Lawsone aldehydes were directly transformed into the biologically important, unique carbon skeleton of chiral methanobenzo[f]azulenes/methanodibenzo[a,d][7]annulenes in high dr and ee and in very good yields by using quinine-thiourea-catalyzed tandem Wittig/intramolecular Michael/intramolecular aldol reactions. This asymmetric catalytic tandem protocol will be highly useful because these final molecules are basic skeletons of important antibiotics. by suing simple substarates abd conditions.

The Front Cover shows that during the exile of Sri Rama, Ravana brahma kidnapped sita devi(Rams's Wife) and took to his land "Lanka" which is an island located in the indian ocean. In order to relieve Sita, Rama build a bridge across the ocean to reach Lanka with his soldiers. Here, the reaction process was correlated with the sethubananam and the particular bridge head bond formed to make the bicycle[3.3.0] octanes through the rearrangement was correlated with the constructed bridge Ramasethu.

Abstract: An ideal stereo selective insertion of in situ generated benzynesion to laws ones through dominofomal[2++2]- cyckiaddition followed by rearrangementis disclosed. The reaction allowed for the preparation of biologically important benzannulated bicyclo[3.3.0] octanes good yield sand with excellent selectivities by suing simple substarates abd conditions.

The Front Cover shows that in an Indian epic, Mahabharat, warrior Arjuna demonstrated excellent skills in archery by aiming at the fish's eye, which was rotating in a circle high above, while looking at its reflection in the water below. Inspired by this, we observed a product specific organocatalytic reaction in a similar fashion and succeeded in aiming for one specific structure among several possibilities. We correlate that, in organocatalysis, the substrates and catalyst are able to produce specific products from many possibilities, emphasizing the concept of memory of product

Abstract: Powerful asymmetric desymmetrization of thiane-3,5-diones through formal [3+3] cycloaddition with alkyl vinyl ketones has been disclosed to access functionally rich 2-thiabicyclo[3.3.1]nonanes in very good yields with excellent enantio- and diastereoselectivities by using organocatalysis.

In this decade, primary organocatalytic species have well demonstrated their importance in a variety of asymmetric reactions. In a similar manner, secondary organocatalytic species (oxazolidinones and aminals) are also blossoming in different asymmetric reactions.

Abstract:Asymmetric synthesis of drug-like functionalized spiro[chroman-3,3′-indolin]-2′-ones 5 containing three contiguous stereocenters with high diastereo- and enantioselectivities was achieved using the reflexive-Michael (r-M) reaction of unmodified hydroxyenals 1 with various (E)-3-alkylideneindolin-2-ones 2 in the presence of (R)-DPPOTMS/AcOH (R)-3/4b as a catalyst at room temperature. Chiral spiro[chroman-3,3′-indolin]-2′-ones 5 were transformed into the functionalized spiranes 7, 9, and 10 in good yields with high selectivity through Wittig, TCRA, acetal protection and reduction reactions, respectively. Supporting evidence for the reaction pathway through the formation of the important catalytic species of aminals was observed through NMR and ESI-HRMS analysis of an ongoing reaction between 1 and (R)-3 in CDCl3 and also shown by the structural requirement in hydroxyenals 1 to generate the aminals with (R)-3 through controlled experiments.

Warriors Arjuna and Srikrishna achieved manyvictories, protecting people from demons and keeping them in good spirits. Similarly, sequential one-pot combination of MCRs and MCC reactions will be victorious over many problems in synthetic organic chemistry.

Abstract:Creating sequential one-pot combinations of multi-component reactions (MCRs) and multi-catalysis cascade (MCC) reactions is a challenging task that has already emerged as a new technology in synthetic organic chemistry. Through one-pot sequential combination of MCRs/MCC reactions, the chemical products (fine chemicals, agrochemicals and pharmaceuticals) that add value to our lives can be produced with less waste and greater economic benefits. Within this emerging area, we describe our recent developments and designs for sequential one-pot MCRs/MCC reactions to facilitate their realization as biomimetics in organic chemistry.

Abstract:The cover picture shows a perspective of organo-click chemistry depicting the bringing together of simple reagents, and amino acid and copper/copper sulfate catalysts to produce spirotriones, which are antioxidant compounds. Unlike conventional methods, organo-click chemistry produces stereospecific products with very good yields in a single operation. Multicomponent reactions catalyzed by amino acids and copper sulfate together with simple reagents depicted here support the potential of a rich variety of chemistries available to the prebiotic world and beyond. For more information see the article by D. B. Ramachary and C. F. Barbas III on p. 5323 ff. The picture was designed by Michael Pique at the Scripps Research Institute.

The cover picture shows how an organocatalytic reductive coupling reaction became a key reaction for the high-yielding two-pot total synthesis of sexually deceptive chiloglottones, regarded as an unexplored class of natural products. Chiloglottones 1-6 were identified in orchids of the genus Chiloglottis, in which they act as pheromones to fool its pollinator, the male wasp Neozeleboria cryptoides

Abstract: Biologically important, less-explored natural products of sexually deceptive chiloglottones, antimicrobial dialkylresorcinols, and their many analogues were synthesized in very good yields in a sequential two-pot manner by using an organocatalytic reductive coupling reaction as the key step. Highlighted on Journal Cover Page

Tetrahedron Lett., 2006, 47, 651-656.
A Novel approach for the two-carbon homologation of aldehydes using amino acid catalysis has been developed and further extended to the generation of pharmaceutically active cyano-esters via four-component reactions in one-pot.