Day: October 13, 2022

Tyagi, Anudishi; Pramanik, Raja; Vishnubhatla, Sreenivas; Ali, Safdar; Bakhshi, Radhika; Chopra, Anita; Singh, Archna; Bakhshi, Sameer published the artcile< Pattern of mitochondrial D-loop variations and their relation with mitochondrial encoded genes in pediatric acute myeloid leukemia>, COA of Formula: C21H27N7Na2O14P2, the main research area is acute myeloid leukemia mitochondrial DNA D loop variation pediatric; AML; D-loop; Mitochondrial DNA; Variations.

Role of mitochondrial DNA variations, particularly in D loop region, remains investigational in acute myeloid leukemia (AML). Consecutive 151 pediatric AML patients were prospectively enrolled from June 2013 to August 2016, for evaluating pattern of variations in mitochondrial D-loop region and to determine their association, if any, with expression of mitochondrial-encoded genes. For each patient, D-loop region was sequenced on baseline bone marrow, buccal swab and mother′s blood sample. Real time PCR was used for relative gene expression of four mitochondrial DNA encoded genes viz. Nicotinamide-adenine-dineucleotide-dehydrogenase subunit 3 (ND3), Cytochrome-B (Cyt-B), Cytochrome c oxidase-I (COX1) and ATP-synthetase F0 subunit-6 (ATP6). Total 1490 variations were found at 237 positions in D-Loop; 1206 (80.9%) were germline and 284 (19.1%) were somatic. Positions 73-263 were identified as a probable hotspot region. G bases appeared to be most stable nucleotide (least number of single base substitutions) whereas T appeared to be most susceptible to variations with germline T-C being the commonest. Gene expression of Cyt-B was found to be significantly higher for any variation (somatic or germline) at positions 16,192 and 16,327 while it was significantly lower for variations at positions 16,051 and 207. Any variation at positions 152, 207 and 513 significantly decreased COX1 expression while those at positions 16,051 and 152 attenuated ATP6 expression. This first study evaluated type and overall pattern of D-loop variations in AML, and also showed that some of these variations in D loop region might have an effect on the mitochondrial-encoded genes which is new and valuable information in AML genomics.

Mutation Research, Fundamental and Molecular Mechanisms of Mutagenesis published new progress about Acute myeloid leukemia. 606-68-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C21H27N7Na2O14P2, COA of Formula: C21H27N7Na2O14P2.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Zhang, Xiaoyong; Mashima, Kazushi; Koyano, Kinko; Sayo, Noboru; Kumobayashi, Hidenori; Akutagawa, Susumu; Takaya, Hidemasa published the artcile< Synthesis of partially hydrogenated BINAP variants>, SDS of cas: 139139-93-8, the main research area is BINAP hydrogenated; crystal structure cyclohexylphosphinylbinaphthyl; mol structure cyclohexylphosphinylbinaphthyl; binaphthyl hydro atropisomeric phosphine ligand.

Three pairs of new axially dissym. diphosphine ligands, (R)-(-)- and (S)-(+)-2,2′-bis(dicyclohexylphosphino)-1,1′-binaphthyl, (R)-(+)- and (S)-(-)-2,2′-bis(diphenylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl and (R)-(-)- and (S)-(+)-2,2′-bis(dicyclohexylphosphino)-5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl, have been synthesized and their absolute configurations have been determined on the basis of an x-ray anal. and CD spectra.

Tetrahedron Letters published new progress about 139139-93-8. 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, SDS of cas: 139139-93-8.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Evans, Sandra; Faller, J. W.; Parr, Jonathan published the artcile< Half-sandwich complexes of ruthenium, rhodium and iridium with a chiral bisphosphine monoselenide>, Product Details of C32H40FeP2, the main research area is ruthenium rhodium iridium half sandwich chiral ferrocenylphosphine selenide chelate; chiral diphosphine mono selenide ligand half sandwich chelate preparation; bidentate chiral diphenylphosphino ferrocenyl phosphine selenide half sandwich complex; crystal structure bidentate chiral diphosphine monoselenide half sandwich chelate; mol structure bidentate chiral diphosphine monoselenide half sandwich chelate.

Neutral and cationic half-sandwich complexes of ruthenium, rhodium and iridium with chiral [(S)-1-[(R)-2-(diphenylphosphino)ferrocenyl]ethyl]di-t-butylphosphine selenide (L, 1) were prepared and characterized. Monoselenation of the com. available chiral bisphosphine afforded potentially bidentate, first enantiomerically pure chiral bisphosphine monoselenide ligand 1, which was reacted with metal half-sandwich dichlorides to give monodentate neutral complexes [Cp*M(L-κP)Cl2] (Cp* = η5-C5Me5; 2, 3; M = Rh, Ir) and [(η6-p-cymene)Ru(L-κP)Cl2] (4). Reaction of 2-4 with NaSbF6 gave cationic complexes [Cp*M(L-κP,κS)Cl]SbF6 (5, 6) and [(η6-cymene)Ru(L-κP,κS)Cl]SbF6 (7), resp., in which the ligand L is bound in a bidentate P,S-mode. The complexes 2-7 were characterized spectroscopically and, for complexes 3, 7 and [Cp*Ir(L-κP,κS)Cl]ClO4 (6′) the crystal structures are reported. The chirality of the ligand influences and controls the metal-centered chirality yielding one of two possible chelate complexes with high diastereoselectivity.

Journal of Organometallic Chemistry published new progress about Bidentate ligands Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation) (complexation). 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, Product Details of C32H40FeP2.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Yang, Bo; Yang, Wu; Guo, Yonghong; You, Lijun; He, Chuan published the artcile< Enantioselective Silylation of Aliphatic C-H Bonds for the Synthesis of Silicon-Stereogenic Dihydrobenzosiloles>, Reference of 139139-86-9, the main research area is rhodium catalyzed enantioselective silylation cyclization styrene derivative arylsilane; silicon stereogenic dihydrobenzosilole containing dehydrocholesterol preparation crystal structure; mol structure silicon stereogenic dihydrobenzosilole containing dehydrocholesterol; C(sp3)−H silylation; asymmetric catalysis; dihydrobenzosiloles; hydrosilylation; silanes.

A Rh(I)-catalyzed enantioselective silylation of aliphatic C-H bonds for the synthesis of Si-stereogenic dihydrobenzosiloles is demonstrated. This reaction involves a highly enantioselective intramol. C(sp3)-H silylation of dihydrosilanes, followed by a stereospecific intermol. alkene hydrosilylation leading to the asym. tetrasubstituted silanes. A wide range of dihydrosilanes and alkenes displaying various functional groups are compatible with this process, giving access to a variety of highly functionalized Si-stereogenic dihydrobenzosiloles in good to excellent yields and enantioselectivities.

Angewandte Chemie, International Edition published new progress about Crystal structure. 139139-86-9 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Reference of 139139-86-9.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Pozo, Juan del; Zhang, Shaochen; Romiti, Filippo; Xu, Shibo; Conger, Ryan P.; Hoveyda, Amir H. published the artcile< Streamlined Catalytic Enantioselective Synthesis of α-Substituted β,γ-Unsaturated Ketones and Either of the Corresponding Tertiary Homoallylic Alcohol Diastereomers>, Quality Control of 277306-29-3, the main research area is enantioselective synthesis substituted unsaturated ketone nitrile allene; tertiary homoallylic alc diastereomer preparation anti HIV agent transformation.

A widely applicable, practical, and scalable strategy for efficient and enantioselective synthesis of β,γ-unsaturated ketones that contain an α-stereogenic center is disclosed. Accordingly, aryl, heteroaryl, alkynyl, alkenyl, allyl, or alkyl ketones that contain an α-stereogenic carbon with an alkyl, an aryl, a benzyloxy, or a siloxy moiety can be generated from readily available starting materials and by the use of com. available chiral ligands in 52-96% yield and 93:7 to >99:1 enantiomeric ratio. To develop the new method, conditions were identified so that high enantioselectivity would be attained and the resulting α-substituted NH-ketimines, wherein there is strong C=N → B(pin) coordination, would not epimerize before conversion to the derived ketone by hydrolysis. It is demonstrated that the ketone products can be converted to an assortment of homoallylic tertiary alcs. in 70-96% yield and 92:8 to >98:2 dr-in either diastereomeric form-by reactions with alkyl-, aryl-, heteroaryl-, allyl-, vinyl-, alkynyl-, or propargyl-metal reagents. The utility of the approach is highlighted through transformations that furnish other desirable derivatives and a concise synthesis route affording more than a gram of a major fragment of anti-HIV agents rubriflordilactones A and B and a specific stereoisomeric analog.

Journal of the American Chemical Society published new progress about Alcohols, homoallylic Role: PRP (Properties), SPN (Synthetic Preparation), PREP (Preparation). 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, Quality Control of 277306-29-3.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Wiest, Johannes M.; Conner, Michael L.; Brown, M. Kevin published the artcile< Synthesis of (-)-Hebelophyllene E: An Entry to Geminal Dimethyl-Cyclobutanes by [2+2] Cycloaddition of Alkenes and Allenoates>, Application In Synthesis of 277306-29-3, the main research area is hebelophyllene E sesquiterpene lactone preparation relative configuration; alkene catalytic enantioselective cycloaddition allenoate; chiral geminal dimethylcyclobutane derivatives preparation diastereoselective reduction; oxazaborolidine catalyst enantioselective cycloaddition alkene allenoate; cycloaddition; enantioselectivity; natural products; small ring systems; total synthesis.

The first synthesis of hebelophyllene E (I) is presented, along with assignment of its previously unknown relative configuration through synthesis of epi-ent-hebelophyllene E. Development of a catalytic enantioselective [2+2] cycloaddition of alkenes and allenoates provides access to the required chiral geminal dimethylcyclobutanes. Key to its success is the identification of a novel oxazaborolidine catalyst which promotes the cycloaddition in high enantioselectivities with good functional-group tolerance (9 examples, up to 97:3 e.r.). Thus, a late-stage cycloaddition using a fully functionalized alkene, followed by a diastereoselective reduction allows a concise entry to this class of natural products.

Angewandte Chemie, International Edition published new progress about [2+2] Cycloaddition reaction (enantioselective, of alkenes and allenoates). 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, Application In Synthesis of 277306-29-3.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Trost, Barry M.; Xu, Jiayi; Schmidt, Thomas published the artcile< Palladium-Catalyzed Decarboxylative Asymmetric Allylic Alkylation of Enol Carbonates>, COA of Formula: C54H42N2O2P2, the main research area is allyl enol carbonate enantioselective regioselective decarboxylative allylic alkylation palladium; ketone homoallylic asym synthesis.

Palladium-catalyzed decarboxylative asym. allylic alkylation (DAAA) of allyl enol carbonates as a highly chemo-, regio-, and enantioselective process for the synthesis of ketones bearing either a quaternary or a tertiary α-stereogenic center has been investigated in detail. Chiral dibenzobarrelene-based diphosphine ligand was found to be optimal in the DAAA of a broad scope of cyclic and acyclic ketones including simple aliphatic ketones with more than one enolizable proton. The allyl moiety of the carbonates has been extended to a variety of cyclic or acyclic disubstituted allyl groups. The mechanistic studies revealed that, similar to the direct allylation of lithium enolates, the DAAA reaction proceeds through an “”outer sphere”” SN2 type of attack on the π-allylpalladium complex by the enolate. An important difference between the DAAA reaction and the direct allylation of lithium enolates is that in the DAAA reaction, the nucleophile and the electrophile were generated simultaneously. Since the π-allylpalladium cation must serve as the counterion for the enolate, the enolate probably exists as a tight-ion-pair. This largely prevents the common side reactions of enolates associated with the equilibrium between different enolates. The much milder reaction conditions as well as the much broader substrate scope also represent the advantages of the DAAA reaction over the direct allylation of preformed metal enolates.

Journal of the American Chemical Society published new progress about Allylic alkylation catalysts, stereoselective. 152140-65-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C54H42N2O2P2, COA of Formula: C54H42N2O2P2.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Shibata, Takanori; Takami, Kyoko; Kawachi, Ai published the artcile< Rh-Catalyzed Enantioselective [2+2] Cycloaddition of Alkynyl Esters and Norbornene Derivatives>, Quality Control of 139139-93-8, the main research area is cyclobutene tetracyclic tricyclic asym synthesis; asym synthesis tricyclononenecarboxylate; rhodium catalyst enantioselective cycloaddition alkynyl ester norbornene.

The enantioselective [2+2] cycloaddition of alkynes possessing an ester functionality, e.g. PhCCCO2Me, and norbornene derivatives proceeded efficiently using a chiral rhodium catalyst. The resulting chiral tri- and tetracyclic cyclobutenes were obtained in moderate to high ee.

Organic Letters published new progress about [2+2] Cycloaddition reaction, stereoselective. 139139-93-8 belongs to class chiral-phosphine-ligands, and the molecular formula is C44H40P2, Quality Control of 139139-93-8.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Feng, Yuting; Viereck, Peter; Li, Shi-Guang; Tsantrizos, Youla S. published the artcile< Rh(I)-catalyzed asymmetric transfer hydrogenation of α-enamidophosphonates to α-aminophosphonates>, Electric Literature of 277306-29-3, the main research area is rhodium catalyst stereoselective transfer hydrogenation enamidophosphonate mechanism; amino phosphonate preparation stereoselective library.

An asym. Rh-catalyzed transfer hydrogenation was developed for the conversion of α-enamidophosphonates to α-aminophosphonates (α-APs) using isopropanol as the hydride donor. This methodol. is amenable to a broad substrate scope. A library of structurally diverse α-APs was synthesized in moderate to good yield and enantiomeric excess, having a methylene moiety at Cβ and aryl, heteroaryl or alkyl side chains.

Tetrahedron published new progress about Enantioselective synthesis. 277306-29-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C32H40FeP2, Electric Literature of 277306-29-3.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate

Burk, Mark J.; Hems, William; Herzberg, Daniela; Malan, Christophe; Zanotti-Gerosa, Antonio published the artcile< A Catalyst for Efficient and Highly Enantioselective Hydrogenation of Aromatic, Heteroaromatic, and α,β-Unsaturated Ketones>, Category: chiral-phosphine-ligands, the main research area is enantioselective hydrogenation ketone ruthenium catalyst.

PhanePhos-ruthenium-diamine complexes catalyze the asym. hydrogenation of a wide range of aromatic, heteroaromatic, and α,β-unsaturated ketones with high activity and excellent enantioselectivity.

Organic Letters published new progress about Alcohols Role: SPN (Synthetic Preparation), PREP (Preparation). 325168-88-5 belongs to class chiral-phosphine-ligands, and the molecular formula is C48H50P2, Category: chiral-phosphine-ligands.

Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate