Category: 617-55-0

Falck, J. R.; Sun, Lumin; Lee, Sang Gyeong; Heckmann, Bertrand; Mioskowski, Charles; Karara, Armando; Capdevila, Jorge published the artcile< Enantiospecific synthesis of 17- and 18-hydroxyeicosatetraenoic acids, cytochrome P450 arachidonate metabolites>, Synthetic Route of 617-55-0, the main research area is hydroxyeicosatetraenoate stereoselective preparation; eicosatetraenoate hydroxy stereoselective preparation; cuprate addition bromobutanediol tosylate.

The title bioactive eicosanoids were prepared from di-Me L-malate by a convergent strategy exploiting the differential reactivity of ethereal dialkylcuprates towards tosylate vs. bromide in the intermediate I.

Tetrahedron Letters published new progress about Addition reaction, regioselective. 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Synthetic Route of 617-55-0.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Sefkow, M. published the artcile< Synthesis of (+)-wikstromol by double alkylation of malic acid>, SDS of cas: 617-55-0, the main research area is lactone lignan wikstromol preparation stereoselective benzylation malic acid derivative.

The synthesis of (+)-wikstromol (I) in six steps, based on two stereoselective benzylations of unnatural malic acid derivatives, is presented. The influence of the alkyl ester on yield and selectivity in the alkylation of malic acid esters is examined

Tetrahedron: Asymmetry published new progress about Benzylation (stereoselective). 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, SDS of cas: 617-55-0.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Kato, Makoto; Toshima, Kazunobu; Matsumura, Shuichi published the artcile< Direct Enzymatic Synthesis of a Polyester with Free Pendant Mercapto Groups>, Recommanded Product: (S)-Dimethyl 2-hydroxysuccinate, the main research area is hexanediol dimethyl mercaptosuccinate enzymic polymerization polyester preparation property; stereochem monomer effect enzymic polym dimethylmercaptosuccinate.

An aliphatic polyester with free pendant mercapto groups was prepared by direct lipase-catalyzed polycondensation of hexane-1,6-diol and di-Me 2-mercaptosuccinate. The polycondensation reaction using immobilized lipase from Candida antarctica (lipase CA) was carried out in bulk at 70 °C without any formation of disulfide or thioester linkages to produce the corresponding polyester with Mw = 14000 g/mol in high yield. The content of free mercapto groups in the polyester could be controlled by copolymerization with other monomers. The obtained polyester was easily crosslinked to form gels by the air oxidation of the pendant thiols to disulfides in DMSO. The effect of stereochem. of the monomers was studied.

Biomacromolecules published new progress about Crosslinking. 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Recommanded Product: (S)-Dimethyl 2-hydroxysuccinate.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Brain, Christopher T.; Chen, Anqi; Nelson, Adam; Tanikkul, Nongluk; Thomas, Eric J. published the artcile< Synthesis of macrocyclic precursors of lankacidins using Stille reactions of 4-(2-iodo-alkenyl)azetidinones and related compounds for ring closure>, Quality Control of 617-55-0, the main research area is lankacidin precursor synthesis Stille coupling iodoalkenylazetidinone ring closure; stereoselective acylation azetidinone lankacidin intermediate preparation; selective cleavage silyl azetidinone lankacidin intermediate preparation; regioselective monodeprotection silyl ether.

In the context of a proposed total synthesis of lankacidins, the synthesis of 4-(2-iodo-alkenyl)azetidinones and their participation in Stille coupling reactions have been investigated. 1-Tert-Butyldimethylsilyl-4-(2-iodoethenyl)azetidinone was found to undergo a Stille coupling reaction with a 3-hydroxy-1-(tributylstannyl)hepta-1,5-diene to give an acceptable yield of the corresponding conjugated diene; but the analogous reaction with a 3-tert-butyldimethylsilyloxy-1-(tributylstannyl)hepta-1,5-diene was unsuccessful. A series of 4-[(E)-2-iodoprop-1-enyl]azetidinones, a ring-opened ester and a lactone were also found to undergo Stille reactions with 3-tributylstannylprop-2-enol albeit with variable yields. Asym. syntheses of Me (2R,3R,5S)-3-tert-butyldimethylsilyloxy-2-methyl-5-(2-trimethylsilylethoxy)methoxy-6-oxohexanoate, (3R,4S)-1-tert-butyldimethylsilyl-4-[(E)-2-iodoprop-1-enyl]-3-methylazetidin-2-one, and (5S,2E,6E)-5-tert-butyldimethylsilyloxy-2-methyl-1-phenylsulfonyl-7-tributylstannylhepta-2,6-diene and their incorporation into macrocyclic precursors of the lankacidins were then investigated. Key reactions were a Julia reaction between the aldehyde and the sulfone to form the 12,13-double-bond, a stereoselective acylation of the azetidinone, and formation of macrocycles using intramol. Stille reactions in the presence of a free hydroxyl group at C(8) (lankacidin numbering).

Tetrahedron published new progress about Acylation, stereoselective. 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Quality Control of 617-55-0.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Zurwerra, Didier; Glaus, Florian; Betschart, Leo; Schuster, Julia; Gertsch, Juerg; Ganci, Walter; Altmann, Karl-Heinz published the artcile< Total synthesis of (-)-zampanolide and structure-activity relationship studies on (-)-dactylolide derivatives>, Synthetic Route of 617-55-0, the main research area is zampanolide asym total synthesis antitumor structure activity relationship; dactylolide asym total synthesis antitumor structure activity relationship.

A new total synthesis of the marine macrolide (-)-zampanolide (I) and the structurally and stereochem. related non-natural levorotatory enantiomer (II) of (+)-dactylolide was developed. The synthesis features a high-yielding, selective intramol. Horner-Wadsworth-Emmons (HWE) reaction to close the 20-membered macrolactone ring of I and II. The β-keto phosphonate/aldehyde precursor for the ring-closure reaction was obtained by esterification of a ω-di-Et phosphono carboxylic acid fragment and a secondary alc. fragment incorporating the THP ring that is embedded in the macrocyclic core structure of I and II. THP ring formation was accomplished through a segment coupling Prins-type cyclization. Employing the same overall strategy, 13-desmethylene-II as well as the monocyclic desTHP derivatives of I and II were prepared Synthetic I inhibited human cancer cell growth in vitro with nanomolar IC50 values, while II, which lacks the diene-containing hemiaminal-linked side-chain of I, is 25- to 260-fold less active. 13-Desmethylene-II as well as the reduced versions of II and 13-desmethylene-II all showed similar cellular activity as II itself. The same activity level was attained by the monocyclic desTHP derivative of I. Oxidation of the aldehyde functionality of II gave a carboxylic acid that was converted into the corresponding N-hexyl amide. The latter showed only micromolar antiproliferative activity, thus being several 100-fold less potent than I.

Chemistry – A European Journal published new progress about Antitumor agents. 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Synthetic Route of 617-55-0.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Christoffers, Jens; Rossler, Ulrich published the artcile< One-pot generation and conversion of trichloroacetimidates for the racemization-free allylation and benzylation of α-hydroxyesters and the enantiopure synthesis of a chiral diglycole>, Recommanded Product: (S)-Dimethyl 2-hydroxysuccinate, the main research area is trichloroacetamidate generation benzylation allylation hydroxy ester; diglycole chiral preparation.

O-Allylations and O-benzylations of the α-hydroxy esters (S)-Et lactate and mandelate and di-Me maleate are performed without racemization. The reagents applied, O-allyl- and O-benzyltrichloroacetimidates ROC(CCl3):NH (R = PhCH2, allyl), are prepared and converted in a one-pot procedure. After protection by benzylation, (S)-(-)-Et lactate is converted by a sequence of carbonyl reduction, alc. activation, ether formation, and deprotection to the optically active diglycole (S,S)-(+)-Bis(2-hydroxypropyl) ether.

Journal fuer Praktische Chemie (Weinheim, Germany) published new progress about Allylation. 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Recommanded Product: (S)-Dimethyl 2-hydroxysuccinate.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Dalidovich, Tatsiana; Nallaparaju, Jagadeesh Varma; Shalima, Tatsiana; Aav, Riina; Kananovich, Dzmitry G. published the artcile< Mechanochemical Nucleophilic Substitution of Alcohols via Isouronium Intermediates>, Recommanded Product: (S)-Dimethyl 2-hydroxysuccinate, the main research area is alc amine mechanochem nucleophilic substitution; tertiary amine preparation; Alcohols; amines; isouronium; mechanochemistry; nucleophilic substitution.

Herein a new mechanochem. method was developed for nucleophilic substitution of alcs. using fluoro-N,N,N’,N’-tetramethylformamidinium hexafluorophosphate (TFFH) and K2HPO4 as an alc.-activating reagent and a base, resp. Alc. activation and reaction with a nucleophile were performed in one milling jar via reactive isouronium intermediates. Nucleophilic substitution with amines afforded alkylated amines in 31-91% yields. The complete stereoinversion occurred for the SN2 reaction of (R)- and (S)-Et lactates. Substitution with halide anions (F-, Br-, I-) and oxygen-centered (CH3OH, PhO-) nucleophiles was also tested. Application of the method to the synthesis of active pharmaceutical ingredients has been demonstrated.

ChemSusChem published new progress about Alcohols Role: RCT (Reactant), RACT (Reactant or Reagent). 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Recommanded Product: (S)-Dimethyl 2-hydroxysuccinate.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Maki, Toshikatsu; Ishihara, Kazuaki; Yamamoto, Hisashi published the artcile< N-Alkyl-4-boronopyridinium Halides versus Boric Acid as Catalysts for the Esterification of α-Hydroxycarboxylic Acids>, Product Details of C6H10O5, the main research area is boric boronic acid catalyst condensation hydroxycarboxylic acid alc; resin bound boronic acid catalyst condensation hydroxycarboxylic acid alc; alpha beta hydroxy ester chemoselective preparation; hydroxybenzoate ester chemoselective preparation; amide preparation; chemoselective condensation alpha beta hydroxy carboxylic hydroxybenzoic acid alc; boronic boric acid catalyst chemoselective condensation hydroxyacid alc; alkyl boronopyridinium halide boric acid catalyst condensation hydroxyacid alc.

α- And β-hydroxycarboxylic and ortho-hydroxybenzoic acids undergo condensation reactions with alcs. in the presence of either boronic acids such as 4-borono-1-methylpyridinium iodide (I) or in the presence of boric acid to yield α-hydroxy or ortho-benzoate esters chemoselectively. When excess alcs. are used to prepare the hydroxyesters, I is the more effective catalyst of those tested, while for esterifications using less than three equivalent of the alc. boric acid is a more effective catalyst. Resin-bound 1-benzyl-4-boronopyridinium chloride is recycled nine times as a catalyst for the dehydrative esterification of mandelic acid in isobutanol to give iso-Bu mandelate in 95-99% conversion. Esterification of α-hydroxy acids with alcs. in the presence of boric acid is preferred to esterification of carboxylic acids; for example, esterification of 2-methyl-2-hydroxypropanoic acid and benzoic acid with one equivalent of 1-octanol in the presence of boric acid yields octyl 2-hydroxy-2-methylpropanoate in 90% and octyl benzoate in 1% yield. I also acts as a catalyst for the condensation of amines and carboxylic acids to give amides; condensation of 5-amino-1-pentanol and benzenebutanoic acid in anisole in the presence of I yields Ph(CH2)3CONH(CH2)5OH (II) in 82% yield; condensation of II with 2-hydroxy-2-methylpropanoic acid in toluene in the presence of boric acid provides Ph(CH2)3CONH(CH2)5OCOC(OH)Me2 in 91% yield.

Organic Letters published new progress about Alcohols Role: RCT (Reactant), RACT (Reactant or Reagent). 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Product Details of C6H10O5.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Paterson, Ian; Findlay, Alison D.; Noti, Christian published the artcile< Total synthesis of (-)-spirangien A, an antimitotic polyketide isolated from the myxobacterium Sorangium cellulosum>, SDS of cas: 617-55-0, the main research area is spirangien A preparation polyketide antimitotic antitumor agent asym synthesis.

An expedient first total synthesis of (-)-spirangien A, a potent cytotoxic and antifungal polyketide of myxobacterial origin, is described. A method for the synthesis of the title compound is reported here. By using a common 1,3-diol intermediate obtained by an efficient aldol-reduction sequence for installation of the C15-C18 and C25-C28 stereotetrads and a reagent-controlled boron aldol coupling followed by spiroacetalization, a highly convergent strategy was developed for construction of the elaborate spiroacetal core. Conversion of this advanced spiroacetal intermediate into (+)-spirangien diene, obtained previously by controlled degradation of spirangien A, was then achieved by installation of the truncated side-chain using an allylboration-Peterson sequence. The total synthesis of (-)-spirangien A was then achieved by the controlled attachment of the unsaturated C1-C12 side-chain, avoiding exposure to light. A Stork-Wittig olefination and double Stille cross-coupling sequence was exploited to install a delicate conjugated pentaene chromophore featuring alternating (Z)- and (E)-olefins, leading initially to the Me ester of spirangien A, which proved significantly more stable than the corresponding free acid. Subsequent careful hydrolysis afforded (-)-spirangien A. validating the relative and absolute configuration.

Chemistry – An Asian Journal published new progress about Absolute configuration. 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, SDS of cas: 617-55-0.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Christopher, John A.; Kocienski, Philip J.; Kuhl, Alexander; Bell, Richard published the artcile< A synthesis of cryptophycin 4 using a planar chiral molybdenum cationic complex>, Application In Synthesis of 617-55-0, the main research area is cryptophycin 4 asym synthesis.

A synthesis of cytotoxic agent Cryptophycin 4 features a new approach to (5S,6R)-5-hydroxy-6-methyl-8-phenyl-(2E,7E)-dienoic acid in which the anti stereochem. between two stereogenic centers is secured by addition of a 1,3-dioxan-4-ylcopper(I) reagent to a planar chiral Mo cationic complex.

Synlett published new progress about Stereoselective synthesis. 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Application In Synthesis of 617-55-0.

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics