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1-Formyl-9H-β-Carboline: A Useful Scaffold for Synthesizing Substituted- and Fused β-Carbolines
Virender Singh, Sanjay Batra
[Abstract] [Purchase Article] [BSP/COS/E-Pub/00007]


Progresses in the Synthesis of A-Ring Phosphine Oxide Synthons for Active Vitamin D3 Analogues
Chao Liu, Yi-Zhen Yin, Long-Qian Tang and Zhao-Peng Liu
[Abstract] [Purchase Article] [BSP/COS/E-Pub/00009]


Stereoselective Ring Opening of Bicyclic Nitroso Diels-Alder Cycloadducts with Carbon Nucleophiles
Stefano Crotti and Mauro Pineschi
[Abstract] [Purchase Article] [BSP/COS/E-Pub/00010]


Structure, Biological Activities and Synthesis of Hyacinthacine Alkaloids and Their Stereoisomers
Thunwadee Ritthiwigrom, Christopher W. G. Au and Stephen G. Pyne
[Abstract] [Purchase Article] [BSP/COS/E-Pub/00011]


Recent Advances in the Retro-Claisen Reaction and Its Synthetic Applications
Marko Jukič, Damjan Šterk and Zdenko Časar
[Abstract] [Purchase Article] [BSP/COS/E-Pub/00013]


Ephedrines and their Acyclic Derivatives
Alejandro Cruz and María Esther Bautista Ramírez
[Abstract] [Purchase Article] [BSP/COS/E-Pub/00014]


Novel Concepts for Organic Syntheses Based on Interfaces and Molecular Machines
Shinsuke Ishihara, Yutaka Wakayama, Nobuya Hiroshiba, Jonathan P. Hill and Katsuhiko Ariga
[Abstract] [Purchase Article] [BSP/COS/E-Pub/00019]


Recent Development on the Synthesis of Benzo[b]- and Naphtho[b]furans: A Review
Halina Kwiecień, Małgorzata Śmist and Monika Kowalewska
[Abstract] [Purchase Article] [BSP/COS/E-Pub/00020]


Molecular Iodine in the Synthesis of Chromone-Type Compounds
Diana C.G.A. Pinto and Artur M.S. Silva
[Abstract] [Purchase Article] [BSP/COS/E-Pub/00021]


Recent Applications of Levoglucosenone as Chiral Synthon
Ariel M. Sarotti, María M. Zanardi, Rolando A. Spanevello and Alejandra G. Suárez
[Abstract] [FULL-TEXT INQUIRY] [BSP/COS/E-Pub/00022]


Catalytic Synthesis of Optically Active β-Amino Acid Derivatives
Pinaki S. Bhadury, Song Yang and Bao-An Song
[Abstract] [Purchase Article] [BSP/COS/E-Pub/00023]



Abstracts


1-Formyl-9H-β-Carboline: A Useful Scaffold for Synthesizing Substituted- and Fused β-Carbolines
Virender Singh, Sanjay Batra
[Purchase Article] [BSP/COS/E-Pub/00007]

β-Carboline represents the core unit of several alkaloids and bioactive agents. This review assimilates the reports pertaining to the synthesis and applications of 1-formyl-9H-β-carbolines for affording 1-substituted, C-1-N-9 and C-1-N-2 fused β-carbolines.
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Progresses in the Synthesis of A-Ring Phosphine Oxide Synthons for Active Vitamin D3 Analogues
Chao Liu, Yi-Zhen Yin, Long-Qian Tang and Zhao-Peng Liu
[Purchase Article] [BSP/COS/E-Pub/00009]

A growing body of biological data indicates that the function of 1α,25-dihydroxyvitamin D3 extends beyond calcium and phosphorus homeostasis. This hormone was also found to regulate cellular differentiation and to play a role in immunoregulatory activity. Extensive researches have been done in the discovery of novel 1α,25(OH)2D3 analogues for the treatment of a diverse range of human diseases, including rickets, psoriasis, renal osteodystrophy, osteoporosis, secondary hyperparathyroidism, cancer, AIDS, rheumatoid arthritis, type 1 diabetes, and Alzheimer’s disease. One of the effective strategy in the construction of the conjugated triene system of vitamin D3 proceeds via Lythgoe’s Wittig-Horner coupling of the A-ring phosphine oxide synthon with the CD-ketone fragment. This article presents a full review of numerous methods developed for the synthesis of A-ring phosphine oxide synthons, including the modifications at the 1-, 2- and 3-positions of the vitamin D A-ring system. The synthetic methods of 19-methylene A-ring phosphine oxide synthons are introduced first, followed by the 19-nor-A-ring phosphine oxide synthons and others.
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Stereoselective Ring Opening of Bicyclic Nitroso Diels-Alder Cycloadducts with Carbon Nucleophiles
Stefano Crotti and Mauro Pineschi
[Purchase Article] [BSP/COS/E-Pub/00010]

Bicyclic oxazines are attractive compounds and valuable synthetic intermediates as they can be easily obtained by hetero Diels-Alder reactions between cyclic dienes and nitroso dienophiles. In particular, the more strained case (i.e. the [2.2.1]-cycloadduct) represents an interesting powerful combination of stability and reactivity as it can be transformed into highly densely functionalized cyclopentene derivatives by a variety of ring-opening reactions. Aim of this article is to summarize the methods used by various chemists for opening of bicyclic oxazines by the formation of a new carbon-carbon bond, to give highly substituted ring systems containing multiple stereocenters. Particular emphasis will be given to regio- and stereoselective procedures, including the most recent developments on less strained [2.2.2]-cycloadduct.
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Structure, Biological Activities and Synthesis of Hyacinthacine Alkaloids and Their Stereoisomers
Thunwadee Ritthiwigrom, Christopher W. G. Au and Stephen G. Pyne
[Purchase Article] [BSP/COS/E-Pub/00011]

This review reports on recent developments on the structure, biological activities and synthesis of hyacinthacine alkaloids and related compounds.
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Recent Advances in the Retro-Claisen Reaction and Its Synthetic Applications
Marko Jukič, Damjan Šterk and Zdenko Časar
[Purchase Article] [BSP/COS/E-Pub/00013]

In 1881, Rainer Ludwig Claisen discovered a carbon-carbon bond-forming reaction between two esters or an ester and a carbonyl compound in the presence of a base. The reaction leads to β-keto esters or β-diketones respectively, and it was later named Claisen condensation, or classic Claisen condensation in the former case, and mixed ('crossed') Claisen condensation in the latter. The reaction now sits firmly in the repertoire of organic synthesis as one of the earliest name reactions. In continuing research, it became evident that the products of this aldol type reaction can be cleaved to produce starting materials. Namely, β-diketone moieties were reported to undergo the retro-Claisen reaction, which is β-dicarbonyl carbon-carbon bond cleavage. Although it was first described as a side, or even parasitic reaction, it was later incorporated into the body of carbon-carbon base-promoted cleavage reactions. Moreover, numerous recent reports have demonstrated the wide selection of methodologies that can be used in these transformations. The scope ranges from various base-mediated or acid-mediated reactions and biocatalyzed transformations, and it extends to recently discovered homogeneous catalyzed reactions. Interestingly, further synthetic applications of retro-Claisen reaction are now being realized, and this is reflected in syntheses of natural products and other fine chemicals. This reaction is nowadays a useful synthetic tool and this review surveys and consolidates the recent literature on the retro-Claisen reaction.
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Ephedrines and their Acyclic Derivatives
Alejandro Cruz and María Esther Bautista Ramírez
[Purchase Article] [BSP/COS/E-Pub/00014]

Ephedra compounds are well known due to their biological activity. They have been widely used in asymmetric synthesis during the last decades. To our knowledge no review about acyclic ephedra derivative compounds has appeared in the literature. In this paper, the synthetic methodologies to access ephedrines and chiral compounds derived from them aresummarized, including those by substitution of the hydroxy group by chlorine, sulfur, nitrogen or phosphorous containing groups. Ephedrines and some ephedra derivatives have displayed biological activity. Some of them have been used as asymmetric inductor ligands or catalysts in asymmetric synthesis. Clearly the ephedra derivatives are potential candidates to be used in both areas.
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Novel Concepts for Organic Syntheses Based on Interfaces and Molecular Machines
Shinsuke Ishihara, Yutaka Wakayama, Nobuya Hiroshiba, Jonathan P. Hill and Katsuhiko Ariga
[Purchase Article] [BSP/COS/E-Pub/00019]

Without doubt, organic chemistry has made significant contributions in improving the qualities of our lives. However, there exists a demand for well-designed molecules of complex structures with additional requirements for low-cost and low-energy production of the materials, which stimulate us to consider innovative concepts in organic synthetic methods. In order to propose innovative methods for next-generation organic synthetic procedures, we present two strategies, (i) organic synthesis within two-dimensional molecular patterns and (ii) organic synthesis driven by molecular machines working at interfaces. For example, synthesis of stereo-regulated polymeric materials in two-dimensional molecular arrays, tip-induced chemical reactions at a solid surface, sequential reactions guided by polymer chains, DNA-nanorobots on two-dimensional DNA origami, ester hydrolysis based on modified behavior of protonated amines at an interface, and several other methods are introduced as pioneering and innovative concepts.
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Recent Development on the Synthesis of Benzo[b]- and Naphtho[b]furans: A Review
Halina Kwiecień, Małgorzata Śmist and Monika Kowalewska
[Purchase Article] [BSP/COS/E-Pub/00020]

Over the past twenty years benzo- and naphtho[b]furan synthesis has been a widely studied topic, certainly due to the presence of this structural unit in many biologically active compounds. Most of the known methods of the synthesis of these heterocycles are based on an intramolecular cyclization of various open-chain precursors. There are four possible ways of the cyclization and they are based on a formation of appropriate furan bonds: O-C2, C2-C3, C3-b and O-b. The following paper presents these four methods of synthesis of benzo[b]- and naphtho[b]furans which have been developed over the last years.
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Molecular Iodine in the Synthesis of Chromone-Type Compounds
Diana C.G.A. Pinto and Artur M.S. Silva
[Purchase Article] [BSP/COS/E-Pub/00021]

Chromones are an important group of heterocyclic compounds due to their important functions in nature and their pharmacological applications. Many efficient syntheses of chromones have been reported through the years but the search for novel methods addressing to the preparation of this type of compounds still remains a relevant topic. Simple and efficient procedures using molecular iodine for the synthesis of these organic molecules have been reported. The uses of catalytic amounts of iodine in cyclodehydration reactions and as additives in oxidative or photooxidative cyclizations are well known approaches for the preparation of new chromone-type compounds. The purpose of this review is to describe the most relevant work on chromone-type compounds using molecular iodine.
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Recent Applications of Levoglucosenone as Chiral Synthon
Ariel M. Sarotti, María M. Zanardi, Rolando A. Spanevello and Alejandra G. Suárez
[FULL-TEXT INQUIRY] [BSP/COS/E-Pub/00022]

Modern organic synthesis requires easily obtainable chiral building blocks that show high chemical versatility for their application in diverse synthetic processes. The main purpose of this review is to present a survey of the scientific literature on levoglucosenone chemistry to provide an up-to-date on different stereoselective synthetic strategies for the construction of biologically important compounds, chiral inductors or templates for organic synthesis.
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Catalytic Synthesis of Optically Active β-Amino Acid Derivatives
Pinaki S. Bhadury, Song Yang and Bao-An Song
[Purchase Article] [BSP/COS/E-Pub/00023]

In continuation to our earlier reviews on organocatalysis, a systematic approach for the synthesis of chiral β-amino acid derivatives in the presence of mainly organocatalysts and transition metal catalysts are described. Asymmetric Mannich reactions catalyzed by proline and bifunctional organocatalysts are explained, whereas metal catalysis based on hydrogenation, Mannich and conjugate additions are elaborated. The resulting β-amino carbonyl moieties are essential structural units of many natural products and are important chiral building blocks for the synthesis of nitrogen-containing bioactive molecules.
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