scholarly journals Monosuccinate ester of melampomagnolide B

2014 ◽  
Vol 70 (3) ◽  
pp. o372-o373
Author(s):  
Venumadhav Janganati ◽  
Narsimha Reddy Penthala ◽  
Nikhil Reddy Madadi ◽  
Sean Parkin ◽  
Peter A. Crooks
Keyword(s):  
Double Bond ◽  
Hydrogen Bonds ◽  
Nucleophilic Addition ◽  
Succinic Anhydride ◽  
Addition Reaction ◽  
Lactone Ring ◽  
Membered Ring ◽  
Reaction Conditions ◽  
Oxobutanoic Acid ◽  
Nucleophilic Addition Reaction

The title monosuccinate derivative of melampomagnolide B [systematic name: 4-(((1aR,7aS,10aS,10bS,E)-1a-methyl-8-methylene-9-oxo-1a,2,3,6,7,7a,8,9,10a,10b-decahydrooxireno[2′,3′:9,10]cyclodeca[1,2-b]furan-5-yl)methoxy)-4-oxobutanoic acid], C19H24O7, was obtained from the reaction of melampomagnolide B with succinic anhydride under nucleophilic addition reaction conditions. The molecule is built up from fused ten-, five- (lactone) and three-membered (epoxide) rings. The internal double bond in the ten-membered ring has thecisgeometry (i.e.it is theEisomer). The lactone ring has an envelope-type conformation, with the (chiral) C atom opposite the lactone O atoms as the flap atom. In the crystal, O—H...O hydrogen bonds link the molecules into chains parallel to theb-axis direction.

scholarly journals 13-(Imidazol-1-yl)-11,13-dihydromelampomagnolide B monohydrate

2013 ◽  
Vol 69 (12) ◽  
pp. o1734-o1735
Author(s):  
Venumadhav Janganati ◽  
Narsimha Reddy Penthala ◽  
Sean Parkin ◽  
Peter A. Crooks
Keyword(s):  
Double Bond ◽  
Hydrogen Bonds ◽  
Michael Addition ◽  
Title Compound ◽  
Lactone Ring ◽  
Membered Ring ◽  
Imidazole Derivative ◽  
Compound C

The title compound, C18H24N2O4·H2O {systematic name: (1aR,7aS,8R,10aS,10bS,E)-5-hydroxymethyl-8-[(1H-imidazol-1-yl)methyl]-1a-methyl-2,3,6,7,7a,8,10a,10b-octahydrooxireno[2′,3′:9,10]cyclodeca[1,2-b]furan-9(1aH)-one monohydrate}, an imidazole derivative of melampomagnolide B was synthesized under Michael addition conditions. The molecule is built up from fused ten-, five- (lactone) and three-membered (epoxide) rings. The internal double bond of the ten-membered ring identifies it as thecisorEisomer. The lactone ring has an envelope-type conformation, with the (chiral) C atom opposite the lactone O atoms as the flap atom. In the crystal, O—H...O, O—H...N and weak C—H...O hydrogen bonds link the molecules (along with water) into sheets parallel to thebcplane.

Nickel-Catalyzed Intramolecular Nucleophilic Addition of Aryl Halides to Aryl Ketones for the Synthesis of Benzofuran Derivatives

Synthesis ◽  
2021 ◽  
Author(s):  
Chen-Liang Deng ◽  
Xiao-Rui Zhu
Keyword(s):  
Nucleophilic Addition ◽  
Addition Reaction ◽  
Aryl Halides ◽  
Reaction Conditions ◽  
Aryl Ketones ◽  
Nucleophilic Addition Reaction ◽  
Standard Reaction

AbstractA nickel-catalyzed intramolecular nucleophilic addition reaction of aryl halides to aryl ketones for the formation of benzofuran derivatives has been developed. A number of substrates bearing electron-donating or electron-withdrawing groups were subjected to the standard reaction conditions, giving the corresponding products in moderate to good yields.

scholarly journals Copper-Catalyzed Ring-Opening Reactions of Alkyl Aziridines with B2pin2: Experimental and Computational Studies

Molecules ◽  
2021 ◽  
Vol 26 (23) ◽  
pp. 7399
Author(s):  
Lucilla Favero ◽  
Andrea Menichetti ◽  
Cosimo Boldrini ◽  
Lucrezia Margherita Comparini ◽  
Valeria Di Bussolo ◽  
...  
Keyword(s):  
Drug Discovery ◽  
Nucleophilic Addition ◽  
Ring Opening ◽  
Addition Reaction ◽  
Computational Studies ◽  
Reaction Conditions ◽  
Ring Opening Reactions ◽  
Computational Data ◽  
Nucleophilic Addition Reaction ◽  
Direct Preparation

The possibility to form new C–B bonds with aziridines using diboron derivatives continues to be a particularly challenging field in view of the direct preparation of functionalized β-aminoboronates, which are important compounds in drug discovery, being a bioisostere of β-aminoacids. We now report experimental and computational data that allows the individuation of the structural requisites and of reaction conditions necessary to open alkyl aziridines using bis(pinacolate)diboron (B2pin2) in a regioselective nucleophilic addition reaction under copper catalysis.

scholarly journals Crystal structure of 13-(E)-(2-aminobenzylidene)parthenolide

2018 ◽  
Vol 74 (11) ◽  
pp. 1543-1546
Author(s):  
Shobanbabu Bommagani ◽  
Narsihma R. Penthala ◽  
Sean Parkin ◽  
Peter A. Crooks
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Dihedral Angle ◽  
Title Compound ◽  
Heck Reaction ◽  
Lactone Ring ◽  
Chair Conformation ◽  
Membered Ring ◽  
Reaction Conditions ◽  
Compound C

The title compound, C21H25NO3[systematic name: (1aR,4E,7aS,8E,10aS,10bR)-8-(2-aminobenzylidene)-1a,5-dimethyl-2,3,6,7,7a,8,10a,10b-octahydrooxireno[2′,3′:9,10]cyclodeca[1,2-b]furan-9(1aH)-one], was synthesized by the reaction of parthenolide [systematic name (1aR,7aS,10aS,10bS,E)-1a,5-dimethyl-8-methylene-2,3,6,7,7a,8,10a,10b-octahydrooxireno[2′,3′:9,10]cyclodeca[1,2-b]furan-9(1aH)-one] with 2-iodoanilineviaHeck reaction conditions. The molecule is composed of fused ten-, five- (lactone), and three-membered (epoxide) rings. The lactone ring shows a flattened envelope-type conformation (r.m.s. deviation from planarity = 0.0477 Å), and bears a 2-aminobenzylidene substituent that is disordered over two conformations [occupancy factors 0.901 (4) and 0.099 (4)]. The ten-membered ring has an approximate chair–chair conformation. The dihedral angle between the 2-aminobenzylidine moiety (major component) and the lactone ring (mean plane) is 59.93 (7)°. There are no conventional hydrogen bonds, but there are a number of weaker C—H...O-type interactions.

Some Analogs of 4-(2',4'-Difluorobiphenyl-4-yl)-2-methyl-4-oxobutanoic Acid: Synthesis and Antiinflammatory Activity

1995 ◽  
Vol 60 (6) ◽  
pp. 1026-1033 ◽  
Author(s):  
Miroslav Kuchař ◽  
Václav Vosátka ◽  
Marie Poppová ◽  
Eva Knězová ◽  
Vladimíra Panajotovová ◽  
...  
Keyword(s):  
Double Bond ◽  
Antiinflammatory Activity ◽  
Acid Synthesis ◽  
Reaction Conditions ◽  
Methyl Group ◽  
Oxobutanoic Acid

Analogs of 4-(2',4'-difluorobiphenyl-4-yl)-2-methyl-4-oxobutanoic acid (I, flobufen), containing a double bond (II, IV, V, VII, VIII) or a methyl group in position 3 (VI) were prepared. Their antiinflammatory activity was evaluated and compared with that of flobufen. None of the mentioned analogs reached the activity of the standard. Isomerization of the unsaturated derivatives is connected with a shift of the double bond, Z-E transformation or lactonization. Reaction conditions and spectra of the compounds prepared are described.

Layer by layer assembled functionalized graphene oxide-based polymer brushes for superlubricity on steel-steel tribocontact

Soft Matter ◽  
2021 ◽  
Author(s):  
Suprakash Samanta ◽  
Rashmi Ranjan Sahoo
Keyword(s):  
Graphene Oxide ◽  
Nucleophilic Addition ◽  
Polymer Brushes ◽  
Addition Reaction ◽  
Layer By Layer ◽  
Functionalized Graphene ◽  
Covalent Functionalization ◽  
Functionalized Graphene Oxide ◽  
Nucleophilic Addition Reaction ◽  
Branched Polyethylenimine

Present study demonstrates a simple and multistep approach for the preparation of covalent functionalization of chemically prepared graphene oxide (GO) by branched polyethylenimine (PEI) through nucleophilic addition reaction to prepare...

scholarly journals 14,15-Didehydrohellebrigenin

2012 ◽  
Vol 68 (6) ◽  
pp. o1614-o1615
Author(s):  
Tong Yu ◽  
Hai-Yan Tian ◽  
Xiao-Feng Yuan ◽  
Shu-Zhi Hu ◽  
Ren-Wang Jiang
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Lactone Ring ◽  
Three Dimensional ◽  
Membered Ring ◽  
Envelope Conformation ◽  
Compound C ◽  
Dimensional Network ◽  
Hydroxy Groups

The title compound, C24H30O5, is the didehydro product of the steroid hellebrigenin (systematic name: 3β,5,14-trihydroxy-19-oxo-5β-bufa-20,22-dienolide). It consists of three cyclohexane rings (A, B and C), a five-membered ring (D) and a six-membered lactone ring (E). The stereochemistry of the ring junctions are A/B cis, B/C trans and C/D cis. Cyclohexane rings A, B and C have normal chair conformations. The five-membered ring D with the C=C bond adopts an envelope conformation. Lactone ring E is essentially planar with a mean derivation of 0.006 (4) Å and is β-oriented at the C atom of ring D to which it is attached. There is an O—H...O hydrogen bond in the molecule involving the hydroxy groups. In the crystal, O—H...O hydrogen bonds link the molecules into chains propagating along [010]. The chains are linked by C—H...O contacts into a three-dimensional network.

Novel Ceric Ammonium Nitrate-Stabilized Maghemite Nanoparticles (CAN-γ-Fe2O3) for Ultrasound Assisted Synthesis of β-Amino Derivatives

2021 ◽  
Author(s):  
Anurag Kumar ◽  
Yifat Harel ◽  
Jean-paul Lellouche ◽  
Suman L. Jain
Keyword(s):  
Carbonyl Compounds ◽  
Addition Reaction ◽  
Ceric Ammonium Nitrate ◽  
Reusable Catalyst ◽  
Maghemite Nanoparticles ◽  
Reaction Conditions ◽  
Recyclable Catalysts ◽  
Nucleophilic Addition Reaction ◽  
Amino Derivatives ◽  
Positively Charged

Abstract Owing to their inherent features like smaller size and higher surface area exposed to reactants, nanoparticles have gained enormous interest and are extensively used as magnetically recyclable catalysts for various organic reactions. Herein, we report highly hydrophilic, non-aggregated, and strongly positively charged (ζ potential: +45.7 mV) ultra-small cerium cations/complexes- stabilized maghemite nanoparticles in water as an efficient and reusable nanoscaled magnetically active catalyst for the nucleophilic addition reaction of various amines with α,β-unsaturated carbonyl compounds to give corresponding β-amino derivatives under ultrasonic irradiation. The developed protocol provides several merits such as high product yields, mild reaction conditions, reusable catalyst and easy workup.

scholarly journals Catalytic Enantioselective Synthesis of 4-Amino-1,2,3,4-tetrahydropyridine Derivatives from Intramolecular Nucleophilic Addition Reaction of Tertiary Enamides

Synlett ◽  
2018 ◽  
Vol 30 (04) ◽  
pp. 483-487 ◽  
Author(s):  
Shuo Tong ◽  
Mei-Xiang Wang
Keyword(s):  
Phosphoric Acid ◽  
Asymmetric Catalysis ◽  
Nucleophilic Addition ◽  
Addition Reaction ◽  
Enantioselective Synthesis ◽  
Chiral Phosphoric Acid ◽  
Substrate Engineering ◽  
Nucleophilic Addition Reaction ◽  
Engineering Strategy ◽  
Acid Catalyzed

A general and efficient method for the synthesis of highly enantiopure 4-amino-1,2,3,4-tetradydropyridine derivatives based on chiral phosphoric acid catalyzed intramolecular nucleophilic addition of tertiary enamides to imines has been developed. We have also demonstrated a substrate engineering strategy to significantly improve the enantioselectivity of asymmetric catalysis

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