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Abstract: Radicamine B 5 was synthesized from p-hydroxy benzaldehyde 7 stereoselectively using acid catalysed amido cyclisation with the help of neighbouring group participation (NGP). Without NGP both radicamine B 5 and its epimer 5-epi radicamine B 6 were obtained. The key steps of the synthesis are Sharpless asymmetric dihydroxylations and acid mediated amido cyclisation. [Copyright &y& Elsevier]

Abstract: The highly stereoselective Grignard addition on chiralimine 8 and opening of chiral epoxide 9 with Grignard reagent have been used as key steps in the stereoselective synthesis of cytotoxic anhydrophytosphingosine pachastrissamine (jaspine B) and N,O,O,O-tetra-acetyl d-lyxo-phytosphingosine. [Copyright &y& Elsevier]

Abstract: A common and stereoselective strategy for the synthesis of N,O,O,O-tetra-acetyl d-ribo-(2S,3S,4R)-phytosphingosine and 2-epi-jaspine B was achieved by using Grignard addition on N-benzyl sugar lactamine and Wittig olefination as key steps. [Copyright &y& Elsevier]

Abstract: A new stereoselective approach for the synthesis of N-benzyl amino(hydroxymethyl)cyclopentitols by using stereoselective allylation on lactamine and RCM from d-ribose has been described and the glycosidase inhibitory activities of these amino cyclopentitols have been studied. [Copyright &y& Elsevier]

Abstract: A Chiron approach for the synthesis of (+)-secosyrin 1 from d-mannitol has been described. The key steps are a stereoselective Wittig reaction and an intramolecular Michael addition on the disubstituted butenolide, leading to a highly stereoselective formation of the tertiary chiral centre of (+)-secosyrin 1. [Copyright &y& Elsevier]

Abstract: The stereoselective synthesis of 6-epi-pentenocin B 3 is described using a stereoselective Grignard reaction and ring-closing metathesis (RCM) as the key steps. [Copyright &y& Elsevier]

Asymmetric syntheses of (1R,1′R,5′R,7′R) and (1S,1′R,5′R,7′R)-1-hydroxy-exo-brevicomins 1 and 2, volatiles of the male mountain pine beetle, and a formal synthesis of (+)-exo-brevicomin 3, a component of the attracting pheromone system of several bark beetles have been achieved. The key steps are Birch reduction of commercially available α-picoline, selective Wittig olefination, and Sharpless asymmetric dihydroxylation. [Copyright &y& Elsevier]

A stereoselective synthesis of 1,4-dideoxy-1,4-imino-d-allitol 1 and formal synthesis of (2S,3R,4S)-3,4-dihydroxyproline was achieved via the addition of vinylmagnesium bromide to the benzylimine derived from (R)-2,3-O-isopropylidene glyceraldehyde followed by N-allylation, ring-closing metathesis (RCM), and dihydroxylation. [Copyright &y& Elsevier]

An efficient and stereoselective synthesis of protected (2R,3R,4S)-4,7-diamino-2,3-dihydroxyheptanoic acid, a constituent of the depsipeptides, callipeltins A and D, from d-ribose is described. [Copyright &y& Elsevier]

An efficient synthesis of enantiopure (−)- and (+)-pentenomycins are described by reductive iodo elimination and ring-closing metathesis (RCM), as the key steps. The first synthesis of the unnatural (+)-isomer is described. [Copyright &y& Elsevier]

Enantioselective synthesis of non-peptidic neurokinin NK1 receptor antagonist L-733,060 is described using ring-closing metathesis as a key step, starting from l-phenylglycine. [Copyright &y& Elsevier]

Abstract: A new strategy for the synthesis of 1,2-dideoxy iminosugar C-glycosides and indolizidines involving highly stereoselective [2,3]-Wittig rearrangement from Garner aldehyde has been developed. This rearrangement yielded an optically pure, highly functionalized key intermediate, which has been further utilized for the synthesis of 5-epi-ethylfagomine, 2-epi-5-deoxyadenophorine, and 5-hydroxymethyl indolizidine. [Copyright &y& Elsevier]

A versatile and efficient method for the preparation of (2S)-2-(hydroxymethyl)-N-Boc-2,3-dihydro-4-pyridone from l-(−)-phenylalanine 2 utilising the aromatic system as a masked β-keto aldehyde was developed. The key step in the sequence is an intramolecular cyclisation of 6 to give 2,3-dihydropyridin-4-ones. [Copyright &y& Elsevier]

Diversity oriented concise asymmetric syntheses of l -2,3- trans -3,4- cis -dihydroxyproline and (3 S ,5 S )-3,4,5-trihydroxypiperidine have been developed from ( R )-glycidol. The key step of the synthesis is Sharpless asymmetric dihydroxylation on enantiomerically pure TBDMS protected allylic alcohol 14 which generates the triol intermediate 15 in excellent de . The (2 R ,3 R ,4 S )-2,3-dihydroxypentanoate derivative 15 was subsequently converted to natural pyrrolidine azasugar 1 and non-natural piperidine azasugar 4 under cascade reaction conditions in good yields. [ABSTRACT FROM AUTHOR]

A concise synthesis of (2 R ,4 R )-4-hydroxyproline ( 1 ) and (2 S ,4 S )-4-hydroxyproline ( 2 ) has been developed in enantiomerically pure form from commercially available starting materials with excellent diastereoselectivity. The tightly bound chelation controlled transition state formed during the 5- exo - tet ring closure reaction is assumed to be the origin of high diastereoselectivity. [ABSTRACT FROM AUTHOR]