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Letters in Organic Chemistry
ISSN: 1570-1786
Letters in Organic Chemistry
Volume 7, Number 2, March 2010
Contents
Graphical
Abstracts Pp.i-v
Samarium Diiodide Catalyzed Aza-Michael Reactions for the
Formation of β-Amino
Amides Pp. 94-97
Iréna Reboule, Sophie Bezzenine-Lafollée,
Jacqueline Collin, Richard Gil and Myriam Martin
[Abstract] [Purchase
Article]
A Convenient Methodology for Nitro-Michael Addition
of Carbonyl Compounds Catalyzed by L-Proline Using Microwave
Heating Pp. 98-102
Alessio Russo, Nicholas E. Leadbeater and
Alessandra Lattanzi
[Abstract] [Purchase
Article]
Microwave-Assisted Studies on the Reactions of the
4-Benzoyl-5-Phenyl-2,3-Dihydro-2,3-Furandione and Derivatives
Pp. 103-105
Esvet Akbas and Ahmet Sener
[Abstract] [Purchase
Article]
Rh(II) Catalyzed Three-Component Reactions of Diazoacetates
with Benzenemethanol and Indane-1, 2, 3-Triones Pp.
106-109
Xin Guo, Jingjing Wang, Liping Yang and
Wenhao Hu
[Abstract] [Purchase
Article]
Optically Active 6-Membered P-Heterocycles: 1-Phenyl-1,2-Dihydrophos-phinine
Oxide and 1-Phenyl-3-Diphenylphosphinoyl-1,2,3,6-Tetrahydro-phosphinine
Oxide Pp. 110-113
Viktória Ujj, Andrea Kerényi,
Andrea Laki, Elemér Fogassy and György
Keglevich
[Abstract] [Purchase
Article]
Direct Experimental Evidence for the Priority of Flexible
Ligand Skeleton in Asymmetric Friedel-Crafts Alkylation of
Indole with Nitroalkenes Pp. 114-120
Han Liu, Neng-Dong Wang and Da-Ming
Du
[Abstract] [Supplementary
Material] [Purchase
Article]
Benzoxazine and Benzodioxine as Indole Isosteres in
Indolocarbazoles Series: Synthesis and Biological Evaluation
Pp. 121-126
Nathalie Ayerbe, Sylvain Routier, Isabelle
Gillaizeau, Sébastien Tardy and Gérard
Coudert
[Abstract] [Purchase
Article]
Synthesis, CI-MS Analyses and Preliminary Biological
Evaluation of a Novel Library of Hydrophobic Persulfide-Spacers
α-Alkyl
Glycosides Pp. 127-135
Hammed H.A.M. Hassan
[Abstract] [Purchase
Article]
Editor’s
Choice
Facile Synthesis of Novel Glycosyl Carboxamide with
Sugar in Furanose and Pyranose form Using Benzotriazole Methodology
Pp. 136-143
Raju R. Kale, Virendra Prasad and
Vinod K. Tiwari
[Abstract] [Purchase
Article]
Regioselective Amination of 3-Bromoindolylmaleimide
with Amines Pp. 144-148
Di-Fa Jiang, Yan-Wu Yang, Zhi-Yu Shao and
Sheng-Yin Zhao
[Abstract] [Purchase
Article]
An Improved Process for the Production of Rivastigmine
Tartrate, a Cholinesterase Inhibitor Pp.
149-154
Vajrala Venkata Reddy, Mandava Venkata Naga
Brahmeswara Rao, Varanasi Ganesh, Adla Vijaya Kumar, Cherukupally
Praveen, Khagga Mukkanti, Ganta Mahesh Reddy and
Ganta Madhusudhan Reddy
[Abstract] [Purchase
Article]
Synthesis of Novel Succinic Acid Derivatives as Potential
Matrix Metalloproteinases Inhibitors and Anticancer Medicine
Pp. 155-158
Huiming Huang, Dan Chen, Shaohua Li and Chengmei
Liu
[Abstract] [Purchase
Article]
Resolution of N-Protected Amino Alcohols
by Porcine Pancreatic Lipase Pp. 159-162
Victoria Magrioti, Irene Fotakopoulou, Nicolaos Athinaios,
Panoula Anastasopoulou, Violetta Constantinou-Kokotou and
George Kokotos
[Abstract] [Purchase
Article]
Phase-Transfer Catalysed Enantioselective Epoxidation
of Estra-Δ5(10),9(11)-diene
Using Chiral Ammonium Salts Derived from Cinchona
Alkaloids Pp. 163-167
Ya-Xi Yang, Zheng Li, Guo-Rong Chen and Yuan-Chao
Li
[Abstract] [Purchase
Article]
Enzymatic Synthesis of Dipeptides in Ionic Liquids
Pp. 168-171
Sanjay V. Malhotra, Chengdong Zhang and Hao Wang
[Abstract] [Purchase
Article]
PEG-400 Catalyzed Reaction for the Synthesis of 2,
4, 6-Triarylpyridines and Crystal Structure of 2,4,6-tris(4’-chlorophenyl)pyridine
Pp. 172-177
Qingpeng He, Jianyong Wang and Ruokun Feng
[Abstract] [Purchase
Article]
Phenyl and Pyridyl Bis-Pyrazoles: Synthesis from the
Bis(β-diketone)
Precursors and Characterization by Analytical and Spectroscopic
Methods Pp. 178-181
Josefina Pons, Arafa Chadghan, Jordi García-Antón
and Josep Ros
[Abstract] [Purchase
Article]
New Hydrazyl Derivatives with Multiple Properties
Pp.182-185
Madalina Tudose, Daniel Angelescu, Gabriela Ionita, Miron
T. Caproiu and Petre Ionita
[Abstract] [Purchase
Article]
Abstracts
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Article]
Samarium Diiodide Catalyzed Aza-Michael Reactions for the
Formation of β-Amino
Amides
Iréna Reboule, Sophie Bezzenine-Lafollée,
Jacqueline Collin, Richard Gil and Myriam Martin
Samarium diiodide is an efficient Lewis acid type catalyst
for the 1,4-addition of aromatic amines onto α,β-unsaturated
N-benzoyl amides affording new β-amino
amides. These reactions are compared with similar aza-Michael
additions involving α,β∼-unsaturated-N-acyloxazolidinones.
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Article]
A Convenient Methodology for Nitro-Michael Addition
of Carbonyl Compounds Catalyzed by L-Proline Using Microwave
Heating
Alessio Russo, Nicholas E. Leadbeater and
Alessandra Lattanzi
Michael addition of aldehydes and ketones to trans-β-nitrostyrene
catalyzed by L-proline was investigated using microwave heating
for rapid optimization of reaction conditions. The products
could be obtained, easily in very short reaction times, high
yields and comparable diastereo- and enantioselectivity with
respect to the original procedures, under simple and more
environmentally benign conditions such as the use of ethanol
as the solvent and only a slight excess of the carbonyl compound.
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Article]
Microwave-Assisted Studies on the Reactions of the
4-Benzoyl-5-Phenyl-2,3-Dihydro-2,3-Furandione and Derivatives
Esvet Akbas and Ahmet Sener
Varieties of heterocyclic compounds were prepared in good
yield from 4-benzoyl-5-phenyl-2,3-dihydro-2,3-furandione under
microwave irradiation conditions. The reaction revealed much
shorter reaction times with comparable yields comparison to
the corresponding thermal conditions.
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Article]
Rh(II) Catalyzed Three-Component Reactions of Diazoacetates
with Benzenemethanol and Indane-1, 2, 3-Triones
Xin Guo, Jingjing Wang, Liping Yang and
Wenhao Hu
A facile synthesis of 2-substituted-2-hydroxyindane-1,3-diones
is reported via the reaction of diazoacetates with
benzenemethanol and indane-1,2,3-triones catalyzed by dirhodium
acetate.
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Article]
Optically Active 6-Membered P-Heterocycles: 1-Phenyl-1,2-Dihydrophos-phinine
Oxide and 1-Phenyl-3-Diphenylphosphinoyl-1,2,3,6-Tetrahydro-phosphinine
Oxide Pp. 110-113
Viktória Ujj, Andrea Kerényi,
Andrea Laki, Elemér Fogassy and György
Keglevich
The antipodes of racemic 1-phenyl-1,2-dihydrophosphinine oxides
1A and 1B were separated
by resolution via formation of a diastereomeric complex
using (–)-(2R,3R)-α,α,α’,α’-tetraphenyl-1,4-dioxaspiro[4.5]decan-2,3-dimethanol
(spiro-TADDOL) 2. The (+)-antipode of 1-phenyl-3-diphenylphosphinoyl-1,2,3,6-tetrahydrophosphinine
oxide 3 was synthesized by the diastereoselective
addition of diphenylphosphine oxide to the α,β-double-bond
of (–)-1,2-dihydrophosphinine oxide 1A.
The new chiral tetrahydrophosphinine oxide (+)-3
served, after double deoxygenation, as a novel P-chiral bidentate
ligand in the corresponding platinum complex.
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[Supplementary
Material] [Purchase
Article]
Direct Experimental Evidence for the Priority of Flexible
Ligand Skeleton in Asymmetric Friedel-Crafts Alkylation of
Indole with Nitroalkenes
Han Liu, Neng-Dong Wang and Da-Ming
Du
Direct experimental evidence for the priority of flexible
ligand skeleton in asymmetric Friedel-Crafts alkylation was
obtained through XRD analysis of flexible ligand/ZnCl2
complex, as well as synthesis of dihydroacridine-linked bis(oxazoline)
ligands with planar rigid scaffold. A transition state model
without NH…π
interaction was proposed for the rigid ligands to interpret
the inversion of absolute configuration.
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Article]
Benzoxazine and Benzodioxine as Indole Isosteres in
Indolocarbazoles Series: Synthesis and Biological Evaluation
Nathalie Ayerbe, Sylvain Routier, Isabelle
Gillaizeau, Sébastien Tardy and Gérard
Coudert
New series of structure based on original benzodioxine and
benzoxazine heterocycles were prepared leading to potential
anticancer lead compounds. In this paper, we described a convenient
approach via a Diels-Alder cycloaddition in order
to efficiently provide three new indole isosteres in indolocarbazoles
series. Their first cytotoxic evaluation was also reported.
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Article]
Synthesis, CI-MS Analyses and Preliminary Biological
Evaluation of a Novel Library of Hydrophobic Persulfide-Spacers
α-Alkyl
Glycosides
Hammed H.A.M. Hassan
We report the synthesis of novel polyether-based polyols derived
from simple glycosides that bear sulfur spacers in the attempt
to potentially provide new antibiotics. The CI-MS demonstrated
the stepwise and successive fission of the sulfide-spacer
groups; however, it does not distinguish between the alditols
having different arrangement of O-(CH2)3-S(CH2)2OH
groups. The investigated compounds exhibited antimicrobial
activities against Staphylococcus aureus, Pseudomonas
aeruginosa, Escherichia coli and antifungal
activities against Candida albicans at a concentration
of 1 mg / ml in DMF.
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Article]
Facile Synthesis of Novel Glycosyl Carboxamide with
Sugar in Furanose and Pyranose form Using Benzotriazole Methodology
Raju R. Kale, Virendra Prasad and
Vinod K. Tiwari
There is an increased demand for significant amounts of carbohydrate
based molecules for complete biological, medicinal, and pharmacological
investigations where tremendous efforts have been made to
develop novel and facile procedure for the synthesis of glycoconjugates
and diverse carboxamides. Limitations with the common approaches
for amide bond formation, including use of hazardous chemicals,
long reaction times, low reaction yields, frequently require
strong basic catalysts, strictly anhydrous conditions, harsh
reaction conditions, expensive and limited availability of
coupling materials, and moreover the less stability of activated
acids warrant the search of a simple, short, and high yielding
amide bond synthetic methodology. Herein, a facile and high
yielding synthesis of novel glycosyl carboxamide with both
furanose and pyranose sugar using benzotriazole methodology
has been developed under mild conditions.
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Article]
Regioselective Amination of 3-Bromoindolylmaleimide
with Amines
Di-Fa Jiang, Yan-Wu Yang, Zhi-Yu Shao and
Sheng-Yin Zhao
3-Bromoindolylmaleimide and bisindolylmaleimide were synthesized
from succinimide in three steps sequnence consisting of bromination,
N-methylation and indole addition in the presence of magnesium
and bromoethane. They were subjeced to the regioselective
amination with substituted amines to provide 3-aminoindolylmaleimides,
3-amino-N-alkylated indolylmaleimides and N-alkylated bisindolylmaleimides
in good yields. The resulting indolylmaleimides represent
a new class of potentially bioactive compounds.
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Article]
An Improved Process for the Production of Rivastigmine
Tartrate, a Cholinesterase Inhibitor
Vajrala Venkata Reddy, Mandava Venkata Naga
Brahmeswara Rao, Varanasi Ganesh, Adla Vijaya Kumar, Cherukupally
Praveen, Khagga Mukkanti, Ganta Mahesh Reddy and
Ganta Madhusudhan Reddy
An improved and scalable process for the production of rivastigmine
tartrate is reported. The improved process provides rivastigmine
tartrate at considerably lower cost and allows the omission
of hazardous chemicals. The overall yield is increased from
4.66% (reported process) to 17% with the improved process.
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Article]
Synthesis of Novel Succinic Acid Derivatives as Potential
Matrix Metalloproteinases Inhibitors and Anticancer Medicine
Huiming Huang, Dan Chen, Shaohua Li and Chengmei
Liu
In this paper we have designed different methods, according
to the differences in nucleophilicity of amino, to conjugate
tartaric acid or malic acid with two kinds of useful intermediates
respectively via amide bond, envisaging they are
promising matrix metalloproteinase inhibitors or anticancer
medicine.
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Article]
Resolution of N-Protected Amino Alcohols
by Porcine Pancreatic Lipase
Victoria Magrioti, Irene Fotakopoulou, Nicolaos Athinaios,
Panoula Anastasopoulou, Violetta Constantinou-Kokotou and
George Kokotos
The resolution of 2-amino alcohols protected by urethane-type
groups either via porcine pancreatic lipase (PPL)
hydrolysis of the corresponding racemic acetates or via
PPL catalyzed transesterification of racemic alcohols was
studied. In both cases, Boc protecting group led to better
chemical yields and enantiopurities than Z and Fmoc protecting
groups. Furthermore, a simple and efficient method for the
synthesis of the medicinally interesting optically pure (R)-2-aminohexadecanol
was developed.
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Article]
Phase-Transfer Catalysed Enantioselective Epoxidation
of Estra-Δ5(10),9(11)-diene
Using Chiral Ammonium Salts Derived from Cinchona
Alkaloids
Ya-Xi Yang, Zheng Li, Guo-Rong Chen and Yuan-Chao
Li
A modified phase-transfer catalysed enantioselective epoxidation
of estra-Δ5(10),9(11)-diene,
an important intermediate of anti-early pregnancy drug mifepristone
1, have been determined and investigated.
Eight chiral ammonium salts (PTC A-H), used
as phase-transfer catalysts, have been synthesized from cinchona
alkaloids. Among them, PTC G and PTC H
have exhibited satisfying catalytic activity to improve the
ratio of α/β
epoxide up to 7:1.
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Enzymatic Synthesis of Dipeptides in Ionic Liquids
Sanjay V. Malhotra, Chengdong Zhang and Hao Wang
Immobilized protease-catalyzed synthesis of peptides from
natural amino acids has been achieved in ionic liquids (ILs).
Three ionic liquids BMIM.PF6,
BMIM.BF4 and EtPy.BF4
have been tested; an effective yet simple and practical method
has been devised. The product yields are comparable with those
seen in molecular solvents. A max yield of 49 % for Boc-Leu-TrpOEt
has been obtained. This study shows that the advantages seen
in organic solvents can also be achieved in ILs, and use of
such medium could provide a viable alternative to organic
and aqueous media for bio-catalysis.
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Article]
PEG-400 Catalyzed Reaction for the Synthesis of 2,
4, 6-Triarylpyridines and Crystal Structure of 2,4,6-tris(4’-chlorophenyl)pyridine
Qingpeng He, Jianyong Wang and Ruokun Feng
An efficient and rapid procedure for synthesizing triarylpyridine
compounds under mild reaction conditions has been described.
Meanwhile, the crystal structure of 2,4,6-tris(4’-chlorophenyl)pyridine
was obtained and determined by X-ray single-crystal diffraction.
The procedure is operationally simple, giving good to high
product yields.
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Article]
Phenyl and Pyridyl Bis-Pyrazoles: Synthesis from the
Bis(β-diketone)
Precursors and Characterization by Analytical and Spectroscopic
Methods
Josefina Pons, Arafa Chadghan, Jordi García-Antón
and Josep Ros
The bis(β-diketone)
compounds, 3,3'-(pyridine-2,6-diyl)bis(1-phenylpropane-1,3-dione)
monohydrated (1a•H2O)
and 3,3'-(pyridine-2,6-diyl)bis(1-(pyridin-2-yl)propane-1,3-dione)
monohydrated (1b•H2O)
were prepared by Claisen condensation of the appropriate ketone
and dimethyl pyridine-2,6-dicarboxylate ester. Compounds 2,6-bis(5-phenyl-1H-pyrazol-3-yl)pyridine
dihydrated (2a•2H2O)
and 2,6-bis(5-(pyridin-2-yl)-1H-pyrazol-3-yl)pyridine
monohydrated (2b•H2O)
were synthesized by reaction of the appropriate bis(β-diketone)
compounds and hydrazine monohydrate.
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New Hydrazyl Derivatives with Multiple Properties
Madalina Tudose, Daniel Angelescu, Gabriela Ionita, Miron
T. Caproiu and Petre Ionita
4-(N’,N’-diphenylhydrazino)-3,5-dinitrobenzoic
acid in reaction with 4-hydroxy-tempo, 4-aminobenzo-15-crown-5,
and 1-bromoacetyl-pyrene, yielded the corresponding esters
or amides, as yellow compounds. These hydrazines, by oxidation
with lead dioxide, converted into the stable hydrazyl free
radicals, with a purple-violet color. Same yellow hydrazines
in reaction with alkali bases are converted into the corresponding
salt of green color. The newly synthesized compounds were
characterized by elemental analysis, IR, UV-Vis, 1H-
and 13C-NMR, and EPR (where
applicable). Acid-base, redox, fluorescence and complexation
properties were also studied and discussed.
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