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The first highly enantioselective intramolecular cyclopropanation of electron-deficient olefins, in the presence of Ru(II) - Pheox catalyst, is reported. The corresponding cyclopropane-fused γ-lactones were obtained in high yields (up to 99%) with excelle

The synthesis of functionalized pyroglutamates 15 and 16 could be achieved by the application of recently developed diastereodivergent asymmetric Michael addition reaction of iminoglycinate 7 to ethyl γ-silyloxycrotonate with >98:2 diastereoselectivity followed by hydrolysis and lactamization. Formal syntheses of (?)-isoretronecanol and (+)-laburnine as well as a concise enantioselective synthesis of (+)-turneforcidine could be achieved from functionalized pyroglutamates 15 or 16.

The asymmetric carbonyl-ene reaction with alkynylogous and vinylogous glyoxylates (1, 2) catalyzed by a binaphthol-derived chiral titanium complex is described. The catalytic asymmetric ene reaction with aldehyde (1) can be applied to the double asymmetric synthesis of isocarbacyclin analogues bearing a 2-allenyl side chain.

A stereodivergent approach for producing piperidine iminosugars has been developed employing a common optically active precursor. The key steps of the synthetic pathway are the double diastereoselection in the asymmetric dihydroxylation of the suitable ch

The scope and limitations of a tandem N-allylation/[2,3]-rearrangement protocol are investigated through the incorporation of a variety of functional groups within an allylic phosphate precursor. This method uses readily accessible N,N-dimethylglycine aryl esters and functionalized allylic phosphates, forming quaternary ammonium salts in situ in the presence of a palladium catalyst. Subsequent enantioselective [2,3]-sigmatropic rearrangement, promoted by the chiral isothiourea tetramisole, generates α-amino acid derivatives with two contiguous stereocenters. The incorporation of electron-withdrawing ester and amide groups gave the best results, furnishing the desired products in moderate to good yields (29-70percent), with low diastereocontrol (typically 60:40 dr) but high enantioselectivity (up to 90:10 er). These results indicate that substrate-catalyst interactions in the proposed transition state are sensitive to the substitution pattern of the substrates.

Ene reductases from the Old Yellow Enzyme (OYE) family reduce the C=C double bond in α,β-unsaturated compounds bearing an electron-withdrawing group, for example, a carbonyl group. This asymmetric reduction has been exploited for biocatalysis. Going beyond its canonical function, we show that members of this enzyme family can also catalyze the formation of C?C bonds. α,β-Unsaturated aldehydes and ketones containing an additional electrophilic group undergo reductive cyclization. Mechanistically, the two-electron-reduced enzyme cofactor FMN delivers a hydride to generate an enolate intermediate, which reacts with the internal electrophile. Single-site replacement of a crucial Tyr residue with a non-protic Phe or Trp favored the cyclization over the natural reduction reaction. The new transformation enabled the enantioselective synthesis of chiral cyclopropanes in up to >99 % ee.

Synthetic methods for the formation of alkenes usually produce the E-alkene because it is more stable. However, in isomerization reaction (double bond migration) that takes place in α, β-unsaturated carbonyl compounds, when these carbonyl compounds are exposed to strong bases, furnish Z-alkenes highly stereoselective depending on the γ-substituent in the α, β-unsaturated carbonyl. This stereoselectivity can be attributed to the known Syn-effect. The synthetic value of this methodology is the achievement of chiral alcohol bearing an electron rich Z-alkene, as well as substituted, which was accomplished via removal of the oxazolidinone moiety under treatment with NaBH4, THF-H2O.

Disclosed are novel retinoid-related orphan receptor gamma (RORγ) modulators and their use in the treatment of diseases mediated by RORγ.

The present invention provides a method of preparing an alkylamine derivates which hardly generates impurities and enables mass production with high purity.

A practical route to 6-bromo-5,7-dihydroxyphthalide 5-methyl ether, a versatile intermediate in the synthesis of hericenones and related bioactive polyphenols, was developed. The synthesis features a combination of tandem Michael addition-Claisen condensation and CuBr2-mediated multi-step reactions. With this product in hand, total syntheses of hericenone J and 5′-deoxohericenone C (hericene A) were achieved.

A practical procedure has been developed for γ-oxygenation of α,β-unsaturated esters by a vinylogous O-nitroso Mukaiyama aldol reaction followed by a one-pot N-O bond heterolysis of the in situ generated γ-aminoxy-α,β-unsaturated esters.

A short, mild, highly diastereo-, regio-, and stereoselective Diels-Alder strategy has been developed for the asymmetric synthesis of (+)albicanol, (+)-albicanyl acetate, (+)-dihydrodrimenin, and (-)-dihydroisodrimeninol.

Upon treatment with homochiral lithium (R)-N-benzyl-N-(α-methylbenzyl)amide, γ-benzyloxy but-2-enoates undergo competitive conjugate addition and γ-deprotonation, while γ-tert-butyldimethylsilyloxy but-2-enoates undergo exclusive conjugate addition. Treatment of γ-benzyloxy or γ-tert-butyldimethylsilyloxy but-2-enamides with lithium (R)-N-benzyl-N-(α-methylbenzyl)amide furnishes exclusively the γ-benzyloxy- or γ-tert-butyldimethylsilyloxy-β-amino amide products of conjugate addition in high de. The γ-tert-butyldimethylsilyloxy-β-amino butanoate products of conjugate addition readily undergo O-desilylation and concomitant cyclisation to furnish 4-[N-benzyl-N-(α-methylbenzyl)amino]-γ-butyrolactone, which may be stereoselectively functionalised via deprotonation and alkylation?to give the corresponding trans-3-alkyl-4-amino-γ-butyrolactones. Alternatively, stereoselective alkylation of γ-benzyloxy- or γ-tert-butyldimethylsilyloxy-β-amino butanoates and butanamides through enolate formation and alkylation following a tandem (via the (Z)-lithium enolate) or stepwise (via the (E)-lithium enolate) protocol gives a range of separable syn- and anti-α-alkyl-β-amino esters and amides. O-Silyl deprotection of the syn- and anti-α-alkyl-β-amino butanoates with TBAF and concomitant cyclisation provide trans-3-alkyl-4-amino-γ-butyrolactones, consistent with epimerisation to the thermodynamically favoured trans-lactone occurring upon deprotection.

A 2,3,4,5-tetrahydro-1H-1,5-benzodiazepine derivative represented by the generalformula (1): [Chemical formula 1] (1) or a pharmaceutically acceptable saltthereof. They are useful as a therapeutic/preventive agent for diabetes, diabeticnephropathy, or glomerulosclerosis.

The present invention provides methods and composition for preparing 4-substituted 3-hydroxybutyric acid derivatives by halohydrin dehalogenase-catalyzed conversion of 4-halo-3-hydroxybutyric acid derivatives. The present invention further provides methods and compositions for preparing 4-halo-3-hydroxybutyric acid derivatives by ketoreductase-catalyzed conversion of 4-halo-3ketobutyric acid derivatives. The present invention also provides methods and compositions for preparing vicinal cyano, hydroxyl substituted carboxylic acid esters.

Semihydrogenation of α,β-unsaturated ynoates and -ynones bearing a γ-alkoxy group can be performed using triphenylphosphine and water. α,β-Unsaturated ynoates were reduced to a mixture of cis and trans α,β-unsaturated enoates, whereas, ynones were reduced to trans α,β-unsaturated enones as the only products.

PCT No. PCT/JP98/03686 Sec. 371 Date Sep. 7, 1999 Sec. 102(e) Date Sep. 7, 1999 PCT Filed Aug. 20, 1998 PCT Pub. No. WO99/31050 PCT Pub. Date Jun. 24, 1999This invention has its objects to provide a process for producing a butyric acid ester derivative of the above general formula (2) which is capable of removing various impurity byproducts whose formation cannot be avoided by the prior art technology, particularly the compound of the above general formula (1), with good efficiency. This invention is related to a process for producing a butyric acid ester derivative of the general formula (2) which comprises treating a mixture containing a compound of the following general formula (1) with an addition reagent capable of adding itself to said ethylenic bond to thereby convert said compound of the general formula (1) to an addition product which can be easily separated from said butyric acid ester derivative of the general formula (2) and a process for producing a butyric acid ester derivative of the general formula (2) which comprises reacting a compound of the general formula (3) with a salt of prussic acid by a flow method. HOCH2-CH=CH-COOR(1)

A 2-deoxy-ribose-type 1-N-iminosugar 5 was synthesized, in multi-gram scale, from fumaric acid monoethyl ester employing Sharpless asymmetric epoxidation followed by a Lewis acid-catalyzed (Yamamoto's aluminum reagent) cyanide epoxy ring-opening reactions.

Aliphatic and aromatic acyl chlorides were efficiently reduced to give the corresponding alcohols when treated with Zn(BH4)2 in the presence of N,N,N',N'-tetramethylethylenediamine.The reactions with other bases were also examined.

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Treatment of β-epoxy-sulphone, -sulphoxide, and -ester with Grignard reagents and copper(I) iodide in diethyl ether-tetrahydrofuran at low temperature leads to rapid ring opening without loss of chirality.

(2E,4Z)-2,4,11-Dodecatrien-1-al (13) has been prepared by using β-bromoallyl alcohol (9) and 1,8-nonadiyne (10) as starting materials. 13 is in agreement with all properties of the natural compound.The synthesis via a Wittig reaction, however, leads to a partial isomerisation of the terminal double bond.

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