(-)-gephyrotoxin-223 was formally synthesized from chiral synthon 1 which has been chemoenzymatically synthesized  in the presence  of candida antartica lipase.

the enzymatic hydrolysis of meso-1,7-diacetoxy-2,6-dimethylheptane 5, prepared from 2,6-dimethylhepta-1,6-diene 6, gave the (2s,6r)-7-acetoxy-2,6-dimethyl-1-heptanol 1, which was transformed to the (2r,6r)-2,6,10-trimethyl-1-undecanol 7. in this manner, the c14 side chain of a-tocopherol was synthesized from 2,6-dimethylhepta-1,6-diene 6 in only 5 steps.

Catalytic asymmetric synthesis of Tamiflu, an important antiinfluenza drug, was achieved. After the catalytic enantioselective desymmetrization of meso-aziridine 3 with TMSN3, using a Y catalyst (1 mol %) derived from ligand 2, an allylic oxygen function and C1 unit on the C=C double bond were introduced through cyanophosphorylation of enone and allylic substitution with an oxygen nucleophile. ...

An efficient and scalable synthesis of various enantiopure 1,3- disubstituted isoindolines is reported. The base catalyzed nucleophilic fragmentation of a rigid overbred template is established with various substrates to afford the corresponding 1,3-disubstituted isoindoline ester, amide, thioate, 1,3-amino alcohol and isoindolylcarboxylic acid. The crucial rigid overbred template is synthesize...

[reaction: see text] A practical organocatalytic process for the synthesis of optically active, highly substituted alpha-hydroxy-ketones was achieved through asymmetric desymmetrization (ADS) of prochiral ketones. The ADS and O-N bond reduction reaction of prochiral ketone with nitrosobenzene in the presence of a catalytic amount of chiral amine or amino acid produced the tandem ADS/O-N bond re...

Synthesis 2001, No. 11, 28 08 2001. Article Identifier: 1437-210X,E;2001,0,11,1737,1741,ftx,en;C03601ss.pdf. © Georg Thieme Verlag Stuttgart · New York ISSN 0039-7881 Abstract: A formal catalytic asymmetric synthesis of (+)-biotin was realized. The key steps involve a catalytic, highly enantioselective and quantitative desymmetrization of a meso cyclic anhydride followed by a one-pot chemoselec...

2.1. Kinetic Resolution of Alcohols and Amines 2987 2.2. Ketene Acylation 2995 2.3. Cycloadditions 2996 2.3.1. â-Lactone Formation 2996 2.3.2. â-Lactam Formation 2997 2.3.3. Ketene Dimerization 2999 2.4. Halogenation 3000 2.5. Baylis−Hillman Reactions 3000 2.6. Desymmetrization of Cyclic Anhydrides 3002 2.7. C-Acylation 3004 2.8. Cyanation 3004 3. Solid Phase Chemistry 3007 3.1. Solution Cataly...

The introduction of a chlorine atom to a carbon center in an enantioselective manner via conventional C-Cl bond formation is difficult. Here we report a new approach to this class of tertiary alkyl chlorides with high optical purities. Instead of forming a new C-Cl bond, our approach involves carbene-catalyzed desymmetrization of 2-chloro-1,3-diols as the key step to set up the chiral carbon ce...

An asymmetric oxa-Michael/Michael cascade reaction of p-quinols and α,β-unsaturated aldehydes provides access to hindered dialkyl ethers. A highly enantioselective oxa-Michael addition of a tertiary alcohol precedes an intramolecular cyclohexadienone desymmetrization, which allows for the concomitant formation of four contiguous stereocenters in a single step. The highly functionalized bicyclic...