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Chiral syntheses

Chirahty at the phosphoms is an unavoidable problem in all phosphorothioate syntheses. The phosphoramidite method produces a mixture of both the and the diastereomers having a small excess of the isomer (53). Although some progress has been made in the chiral synthesis of dinucleoside phosphorothioates, low yields have limited the utility of these approaches. The chiral center may be eliminated by replacing the other, nonbridging oxygen with sulfur. Avoidance of the chirahty problem is one reason for the interest in phosphorodithioates. [Pg.262]

A second, conceptually distinct chiral synthesis of monobactams was developed from P-hydroxy amino acids. As shown in Figure 2, cycli2ation of the acylsulfamate of an amino-protected 0-mesylserine derivative (14, R = H) leads directiy to the monobactam (15). This methodology was also appHed to the synthesis of 4a- (15, R = CH ) and 4P-methyl monobactams from L-threonine and aHothreonine, respectively (17). The... [Pg.62]

A final example of this synthetic methodology is the chiral synthesis of the cyclopenta[c]pyridine ring system of (-)-plectrodorine 43. Oxazole 41 was heated in o-... [Pg.329]

Consonant with the present interest in chiral synthesis, two additional contributions can be cited. Sih al utilized a combined microbiological and organic chemical sequence in which key chirality establishing steps include the conversion of to chiral, but unstable, 18 by enzymic reduction using the fungus Diplodascus uninucleatus. Lower side-chain synthon was prepared by reduction of achiral with Pencillium decumbens. [Pg.6]

Node and Fuji have developed a new chiral synthesis of various alkaloids using chiral nitroalkene, fS -( - -3-methyl-3-( 3 -nitrovinyl -o-valerolactone Scheme 8 11 shows a total synthesis of f-i-physosdgmine, a principM alkriloid of the CMabar bean The key nitroalkene is prepared by asymmetric nitroolefinadon of ct-methyl-o-lactone using a chirM enamine fsee... [Pg.246]

Further utility of the Andersen sulphoxides synthesis is demonstrated by the preparation of optically active unsaturated sulphoxides which were first prepared by Stirling and coworkers359 from sulphinate 276 and the appropriate vinylic Grignard reagents. Later on, Posner and Tang360 prepared in a similar way a series of ( )-l-alkenyl p-tolyl sulphoxides. Posner s group accomplished also the synthesis of (+)-(S)-2-(p-tolylsulphinyl)-2-cyclopentenone 287, which is a key compound in the chiral synthesis of various natural products361 (equation 159). [Pg.299]

Keywords bis(oxazoiine) copper complexes, Lewis-acid catalysts for carbo-cyclic and hefero-Diels-Alder reaction, chiral synthesis... [Pg.304]

This suite of BVMOs is available via whole-cell expression systems and represents a complementary platform of biocatalysts for diverse applications in chiral synthesis. Representatives of this collection were utilized in the enantiodivergent synthesis of the indole alkaloids alloyohimbane and antirhine from a fused bicyclic precursor (Scheme 9.19) [151]. [Pg.247]

The regiochemical course reacting saturated ketones depended on the substitution pattern of the a-positions. In most cases, the intermediate oxime had an anti N-OH function with respect to the chain branched a-position. Consequently, the more substituted alkyl group preferentially migrates. This advantage was utilized for synthesizing the spiro a-amino-e-caprolactam (202 203, Scheme 38) [12c], the Mexican bean beetle azamacrolide allomone (205 206, Scheme 39) [44 a], in a key step of the chiral synthesis of benzomorphanes... [Pg.157]

Up to the present, fifteen enantiomers have been synthesized among the thirty-two carba-sugars theoretically predicted. Four of them have been prepared from the antipodes of the Diels-Alder adduct 29, two were obtained from quebrachitol, and a chiral synthesis, starting from true sugars, provided the thirteen enantiomers. [Pg.36]

Among the known enantiomers of carba-sugars, thirteen have been synthesized by a chiral synthesis starting from a true sugar the four modifica-... [Pg.89]

The above sequence was demonstrated on racemic onti-mercaptol alcohol 14 as well on a small amount of optically pure 14 (separated by chiral HPLC separation) and the chiral centers of 14 were completely retained, as expected (Scheme 5.6) [8]. With proof of concept for the ring formation strategy, some efforts were put into developing a chiral synthesis of 14, as shown in Scheme 5.7. [Pg.149]

The Cp2TiPh-catalyzed coupling reaction of the dials also gives the cyclic diols with excellent diastereoselectivity. The protocol is extended to the chiral synthesis as shown in Scheme 16 [50,51]. [Pg.73]

Chiral Synthesis of Pharmaceutical Intermediates Using Oxynitrilases... [Pg.9]

Hydroxynitrile lyases (HNLs or oxynitrilases) catalyze C—C bond-forming reactions between an aldehyde or ketone and cyanide to form enantiopure cyanohydrins (Figure 1.15), which are versatile building blocks for the chiral synthesis of amino acids, hydroxy ketones, hydroxy acids, amines and so on [68], Screening of natural sources has led to the discovery of both... [Pg.25]

D-Pantolactone and L-pantolactone are used as chiral intermediates in chemical synthesis, whereas pantoic acid is used as a vitamin B2 complex. All can be obtained from racemic mixtures by consecutive enzymatic hydrolysis and extraction. Subsequently, the desired hydrolysed enantiomer is lactonized, extracted and crystallized (Figure 4.6). The nondesired enantiomer is reracemized and recycled into the plug-flow reactor [33,34]. Herewith, a conversion of 90-95% is reached, meaning that the resolution of racemic mixtures is an alternative to a possible chiral synthesis. The applied y-lactonase from Fusarium oxysporum in the form of resting whole cells immobilized in calcium alginate beads retains more than 90% of its initial activity even after 180 days of continuous use. The biotransformation yielding D-pantolactone in a fixed-bed reactor skips several steps here that are necessary in the chemical resolution. Hence, the illustrated process carried out by Fuji Chemical Industries Co., Ltd is an elegant way for resolution of racemic mixtures. [Pg.86]


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0-Allenic alcohols, chiral, synthesis

1 - -1,2,3,4-tetrahydroisoquinolines chiral synthesis

Alcohols chiral synthesis

Aldolase-catalyzed synthesis, chiral

Allylic alcohols chiral hydroperoxide synthesis

An Overview of Enzymes Used in Chiral Synthesis

Application in the Synthesis of Chiral Conjugate Oligomers and Polymers

Applications of Chiral Sulfoxides as Stereocontrol Elements in Organic Synthesis

Asymmetric aza Diels-Alder reactions synthesis of tetrahydroquinoline derivatives using a chiral lanthanide Lewis acid as catalyst

Asymmetric hydrogenation chiral amine synthesis

Asymmetric synthesis chiral lithium amide reactions

Asymmetric synthesis from chiral pool compounds

Asymmetric synthesis in chiral

Asymmetric synthesis of chiral alkaloids

Asymmetric synthesis of chiral isoquinolines

Asymmetric synthesis of chiral piperidines

Asymmetric synthesis via chiral organoborane

Asymmetric synthesis via chiral organoboranes

Asymmetric synthesis with chiral auxiliaries

Asymmetric synthesis with chiral catalysts

Asymmetric synthesis with chiral reagents

Asymmetric synthesis with chiral sulfur reagent

Asymmetric synthesis, chiral auxiliaries

Binaphthyls chiral synthesis

Bioactive natural products chiral synthesis

Biooxidations in Chiral Synthesis

Biotransformations Green Processes for the Synthesis of Chiral Fine Chemicals

Biphenyl chiral synthesis

Biphenyls chiral synthesis

Braun reagent chiral synthesis

Bryostatin 7 synthesis chiral auxiliaries

Butenolides chiral synthesis

Carbaaldopyranoses synthesis chiral sources for

Carbapenems, chiral synthesis

Carbonyl reduction chiral compound stereoselective synthesis

Carboxylic acids, a-hydroxyasymmetric synthesis chiral

Carboxylic acids, chiral, enzymatic synthesis

Chemical synthesis chiral sensitivity

Chemical synthesis chiral substituents

Chiral -cyano alcohols synthesis

Chiral 2,3-dihydropyrroles synthesis

Chiral 2-amino alcohol synthesis

Chiral Aldehydes as Dienophiles Synthesis of Long-Chain Sugars

Chiral Amine Synthesis: Methods, Developments and Applications. Edited by Thomas C. Nugent

Chiral Auxiliaries and Ligands in Asymmetric Synthesis

Chiral Grignard reagents, synthesis

Chiral Organic Synthesis

Chiral Zirconium Catalysts for Enantioselective Synthesis

Chiral acetals asymmetric synthesis from

Chiral acylsilanes synthesis

Chiral alcoholates, asymmetric synthesis

Chiral alcohols asymmetric synthesis

Chiral alkaloids asymmetric synthesis

Chiral alkoxy-allenes synthesis

Chiral alkyl halides synthesis

Chiral alkylamines synthesis

Chiral allylboronates synthesis

Chiral amides, synthesis

Chiral amines asymmetric synthesis

Chiral amines synthesis

Chiral aminoalkylphosphinic acids, synthesis

Chiral asymmetric synthesis

Chiral auxiliaries Strecker amino acid synthesis

Chiral auxiliaries drug synthesis

Chiral auxiliaries organic synthesis

Chiral auxiliaries sulfone synthesis

Chiral auxiliaries synthesis

Chiral aziridines synthesis

Chiral biaryls asymmetric synthesis

Chiral biaryls synthesis

Chiral building blocks asymmetric synthesis

Chiral building blocks in synthesis of 3-piperidinol

Chiral building blocks, synthesis

Chiral calixarenes synthesis

Chiral carbocycles, synthesis

Chiral cavities asymmetric syntheses

Chiral centers, enantiospecific synthesis

Chiral centre synthesis

Chiral compound stereoselective synthesis

Chiral compound stereoselective synthesis reduction products

Chiral compound stereoselective synthesis whole-cell biocatalysts

Chiral compound synthesis dehydrogenases

Chiral compounds biocatalytic synthesis methods

Chiral compounds enantioselective synthesis

Chiral compounds, synthesis

Chiral crown ethers synthesis

Chiral cyclobutane synthesis

Chiral cyclohexanones, synthesis

Chiral cyclohexylamines. synthesis

Chiral dioxetanes, stereoselective synthesis

Chiral dopa synthesis

Chiral drug intermediates synthesis

Chiral endoperoxides, synthesis

Chiral fluoxetine synthesis, using

Chiral fragments synthesis

Chiral glycerol ethers synthesis

Chiral glycol ethers synthesis

Chiral hydroperoxides synthesis

Chiral in peptide synthesis

Chiral isoquinolines synthesis

Chiral lactones synthesis

Chiral ligand asymmetrical synthesis

Chiral ligands chlorohydrin synthesis

Chiral lithium amides in asymmetric synthesis

Chiral metal complexes asymmetric synthesis

Chiral metallocenes, synthesis

Chiral methyl groups synthesis

Chiral molecules synthesis

Chiral natural products synthesis

Chiral pharmaceuticals, synthesis

Chiral phosphate synthesis

Chiral phosphines, synthesis

Chiral phosphinites, synthesis

Chiral phosphoranes synthesis

Chiral piperidines synthesis

Chiral pool asymmetric synthesis with

Chiral pool enantioselective syntheses with

Chiral pool synthesis

Chiral pregabalin synthesis

Chiral primary amine synthesis, steps

Chiral propargyl alcohol synthesis

Chiral pyrrolidines synthesis from carbohydrates

Chiral quaternary centers, enantioselective synthesis

Chiral reagents, amino acid synthesis with

Chiral sesquiterpenes synthesis

Chiral sitagliptin synthesis

Chiral solvents asymmetric synthesis

Chiral sulfoxides organic synthesis

Chiral sulfoxides, synthesis

Chiral sulphones synthesis

Chiral sulphoxides synthesis

Chiral synthesis Corey-Bakshi-Shibata reduction

Chiral synthesis asymmetric aminohydroxylation

Chiral synthesis naproxen

Chiral synthesis of amino acid

Chiral synthesis of bioregulators

Chiral synthesis of semiochemicals

Chiral synthesis quinolines

Chiral synthesis reagent control

Chiral synthesis substrate control

Chiral synthesis technique

Chiral synthesis, small molecule drug

Chiral synthesis, using enzymes

Chiral template synthesis

Chiral tertiary alcohols asymmetric synthesis

Chiral triazolium syntheses

Chiral vinyl ether alcohols synthesis

Chiral, nonracemic epoxides, synthesis

Chirality Transfer in Polynuclear Complexes Enantioselective Synthesis

Chirality asymmetric synthesis

Chirality enantioselective synthesis

Chirality synthesis

Cinchona-Derived Chiral Phase-Transfer Catalysts for Other Asymmetric Synthesis

Cinchona-Derived Chiral Poly(Phase-Transfer Catalysts) for Asymmetric Synthesis

Derived Chiral Phase-Transfer Catalysts for Amino Acid Synthesis

Desymmetrization and Enzymatic Strategies for Chiral Propargyl Alcohol Synthesis

Diastereoselective synthesis aldol reactions, chiral enolates

Diastereoselective synthesis chiral auxiliaries

Diastereoselective synthesis chiral building blocks

Diastereoselectivity chiral auxiliaries, drug synthesis

Drug synthesis chiral building blocks

Enantiomers chiral auxiliaries, drug synthesis

Enantioselective Synthesis Mediated by Chiral Crystals of an Achiral Organic Compound in Conjunction with Asymmetric Autocatalysis

Enantioselective Synthesis or Resolution of Chiral Ligands

Enantioselective synthesis chiral agents

Enantioselective synthesis chiral metal complexes

Enantioselective synthesis, chiral memory

Enantioselective synthesis, chiral starting

Enzymatic synthesis chiral alcohols, kinetic resolution

Enzymatic synthesis chiral amine

Epoxides chiral, synthesis

Ethers, Taddol, Nobin and Metal(salen) Complexes as Chiral Phase-Transfer Catalysts for Asymmetric Synthesis

FERRIER Chiral cyclohexanone synthesis

Ferrocenes chiral metallocene synthesis

From metal cyanides chiral synthesis

Functionalized chiral amine synthesis

General Procedures for the Synthesis of Enantiomerically Enriched Aza MBH Type Adducts Catalyzed by Chiral Sulfide

Germanes chiral, synthesis

Glycidic acid esters chiral, synthesis

Glycosylamines as Auxiliaries in Stereoselective Syntheses of Chiral Amino Compounds

HMG-CoA Reductase Inhibitors Aldolase-Catalyzed Synthesis of Chiral Lactol

Hydrogen peroxide chiral hydroperoxide synthesis

Ibuprofen, chirality and green synthesis

Ionic chiral auxiliaries synthesis

Iron complexes, dienyladdition of chiral nucleophiles synthesis

Keto esters chiral compound stereoselective synthesis

Magnesium bromide, isobomyloxyhydride donor use in chiral syntheses

Mevinolin synthesis, via chiral acetals

Monofunctional Epoxides as Chiral Building Blocks for the Synthesis of Biologically Active Compounds

Optically active chiral amines, synthesis

Organic synthesis chiral boranes

Other Chiral Phase-Transfer Catalysts for Asymmetric Synthesis

Oxazolidinone, chiral dioxetane synthesis

Oxygen chiral phosphate esters synthesis

Oxygen chiral phosphate synthesis

P-Lactams synthesis via chiral ketenes or imines

Phosphorothioates chiral synthesis

Pinene and Derivatives for Stereospecific Syntheses of Chiral Monoterpenes

Poly chiral synthesis from

Propranolol, chiral synthesis

Pyrrolizidine alkaloids chiral synthesis

Quinolizidine alkaloids, chiral synthesis

Reagent controlled asymmetric synthesis chirality

SAMP/RAMP chiral auxiliaries synthesis

SYNTHESIS OF AXIALLY CHIRAL BIARYLS

Secondary chiral Grignard reagents, synthesis

Selective redox reaction chiral synthesis

Semiochemicals chiral synthesis

Sitagliptin Enzymatic Synthesis of Chiral Amine

Stereocontrolled synthesis of chiral

Stereoselective Syntheses of Chiral Heterocycles

Stereoselective Syntheses of Chiral Piperidines via Addition Reactions to 4-Pyridones

Stereoselective synthesis from chiral pool

Stereoselectivity chiral dioxetane synthesis

Stereoselectivity chiral hydroperoxide synthesis

Study 6.21 Asymmetric synthesis in crystals application of chiral auxiliaries

Substrate Controlled Chiral Amine Synthesis via C H Amination

Substrate controlled chiral amine synthesis

Sugars as Chiral Starting Materials in Enantiospecific Synthesis

Sulfinimines, chiral asymmetric synthesis

Sulfoxides chiral sulfoxide synthesis

Syntheses Using Carbohydrates as Chiral Educts (Chirons)

Synthesis chiral dioxetanes

Synthesis chiral drugs

Synthesis chiral lithium amide deprotonations

Synthesis chiral nematics

Synthesis chiral propargylic alcohol

Synthesis chiral template strategy

Synthesis chirally selective organic

Synthesis of Chiral Amines

Synthesis of Chiral Amines via Tandem Hydroamination Hydrosilylation

Synthesis of Chiral Aziridines

Synthesis of Chiral Compounds

Synthesis of Chiral Cyanohydrins Using Hydroxy Nitrile Lyases (HNLs)

Synthesis of Chiral Esters

Synthesis of Chiral Ketones

Synthesis of Chiral Nitridomanganese Complex

Synthesis of Chiral Nitriles

Synthesis of Chiral Oxirans

Synthesis of Chiral Phthalimidine Derivatives

Synthesis of Chiral Smectic Liquid Crystals

Synthesis of Naproxen (Chiral Auxiliary Approach)

Synthesis of Non-Chiral Smectic Liquid Crystals

Synthesis of Optically Active syn Aldols Using Chiral Auxiliaries

Synthesis of Pharmaceutically Relevant Chiral Tetrahydrofurans

Synthesis of chiral molecules

Synthesis of chiral polymers

Synthesis of chiral sulfoxides

Synthesis of chiral, non-racemic cyclopropanes

Synthesis, asymmetric chiral from achiral

Terpenes Chiral auxiliary synthesis

The Synthesis of Chiral Molecules

The Synthesis of Chiral Nematic Liquid Crystals

The Synthesis of Chiral Sulfoxides through Nucleophilic Displacement at Sulfur

Two-Center Chiral Phase-Transfer Catalysts for Asymmetric Synthesis

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