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Letters in Organic Chemistry
ISSN: 1570-1786
Letters in Organic Chemistry
Volume 4, Number 8, December 2007
Preparation of an Artificial Ribonucleoside with
pyrimido[4,5 d]pyrimidine- 2,4,5,7-(1H,3H,6H,8H)-tetraone
as a Base and its Discriminating Ability for Natural Nucleosides
Pp. 530-534
Taisuke Hirano, Kenji Kuroda, Hidehiko Kodama, Masanori
Kataoka and Yoshihiro Hayakawa
[Abstract]
Palladium-Catalyzed Cross-Coupling Reaction of Arenediazonium
Salts with Alkyl Chloroformates Pp. 535-538
Rolando Pérez, Daniela de Luna Martins, Lúcia
C.S. Aguiar, Heiddy M. Alvarez, L. Cardozo-Filho, Aline V.
Coelho and O.A.C. Antunes
[Abstract]
Synthesis and Transformation of Thiazolomorphinanedienes
Pp. 539-543
Miklós Tóth, Zsuzsanna Gyulai, Sándor
Berényi and Attila Sipos
[Abstract]
Vanadium-Substituted Keggin Type Heteropolyacid are
Used for the Selective Oxidation of Sulfides to Sulfoxides
and Sulfones Using Hydrogen Peroxide Pp. 544-549
G. Romanelli, D. Bennardi, V. Palermo, P. Vázquez
and P. Tundo
[Abstract]
Excellent Exo/Endo-Selectivity in the 1,3-Dipolar
Cycloaddition of Cyclic Azomethine Ylide: Exploring the Facile
Investigation of Cocaine Antagonists Pp. 550-552
Joydev K. Laha
[Abstract]
Total Synthesis of (±)-Euryfuran
Through Ti(III) Catalyzed Radical Cyclization Pp.
553-555
Antonio Rosales, Cristóbal López-Sánchez,
Míriam Alvarez Corral, Manuel Muñoz-Dorado and
Ignacio Rodríguez-García
[Abstract]
Enantiospecific Synthesis of (–)-Radicamine
B Pp. 556-558
Chunyan Liu, Junchao Gao, Guang Yang, Richard H. Wightman
and Shende Jiang
[Abstract]
Synthesis of Multivalent Galactosides with High Affinity
for the Hepatic Asialoglycoprotein Receptor Pp. 559-562
Li Hai, Jiao Lu, Zhi-Rong Zhang, Shou-Zhu Liao, Jin-Cheng
Yang and Yong Wu
[Abstract]
The Modular Synthesis of Chiral N-Heterocyclic Carbene
Precursors Pp. 563-566
Attila Paczal and András Kotschy
[Abstract]
The Novel One-Pot Synthesis of Functionalized Vinyl
Sulfides Using Triphenylphosphine Catalyzed Nucleophilic Addition
of Thiols to Acetylenes Pp. 567-570
Robabeh Baharfar, Seyed M. Baghbanian, Roghayeh Hossein
nia and Hamid R. Bijanzadeh
[Abstract]
Enantioselective Alkynylation of Aromatic Aldehydes
Catalyzed by New C2-Symmetric
Bis-Schiff Base Amino Alcohol Pp. 571-575
Min Hong and Qi-dong You
[Abstract]
KF-Al2O3
Promoted Synthesis of Fully Substituted New Indeno and Naphtho-
Fused Thiophenes Under Solvent Free Conditions by Controlled
Microwave Heating Pp. 576-584
Firouz M. Moghaddam, Hamdollah Saeidian, Zohreh Mirjafary
and Azam sadeghi
[Abstract]
N-Acylbenzotriazole Mediated Synthesis of
Some Methacrylamido Amino Acids Pp. 585-587
Deniz Hür, Sultan F. Ekti and Rdvan Say
[Abstract]
A Facile Synthesis of Lipo-Chitopentaose Nodulation
Factor Pp. 588-589
G.-L. Huang and Kongliang Wong
[Abstract]
Aminocarbonylation of 2-Iodothiophene: High-Yielding
Synthesis of Thiophen-2-yl-glyoxylamides Pp. 590-594
Attila Takács, Andrea Petz, Balázs Jakab
and László Kollár
[Abstract]
Tris(2-Hydroxyphenyl)Methanes: Ligand with High Affinity
Toward a Chloride Anion Pp. 595-600
Tatsunori Sato, Shintaro Higuchi and Kazuaki Ito
[Abstract]
Synthesis and Antitumor Activities of 3-Substituted
1-(5 formylfurfuryl) indolin-2-one Derivatives Pp.
601-605
Fusheng Zhou, Jianbin Zheng, Xiaochun Dong, Zhiwen Zhang,
Lingling Zhao, Xianyi Sha, Lin Li and Ren Wen
[Abstract]
Abstracts
[Back to top]
Preparation of an Artificial Ribonucleoside
with pyrimido[4,5 d]pyrimidine- 2,4,5,7-(1H,3H,6H,8H)-tetraone
as a Base and its Discriminating Ability for Natural Nucleosides
Taisuke Hirano, Kenji Kuroda, Hidehiko Kodama, Masanori
Kataoka and Yoshihiro Hayakawa
An artificial ribonucleoside with pyrimido[4,5-d]pyrimidine-2,4,5,7-(1H,3H,6H,8H)-tetraone
(PPT) as a nucleobase was prepared, and its binding affinity
for natural nucleosides, e.g., 2’-deoxyadenosine,
2’-deoxycytidine, 2’-deoxyguanosine, and thymidine
derivatives, was investigated. This investigation revealed
that, as expected, the nucleoside with PPT has good binding
affinity for the four natural nucleosides to form with them
some stable complexes in dimethyl sulfoxide, though the structure
of the complex is not clear yet. Thus, this artificial nucleoside
has high potential as a universal nucleoside.
[Back to top]
Palladium-Catalyzed Cross-Coupling Reaction of
Arenediazonium Salts with Alkyl Chloroformates
Rolando Pérez, Daniela de Luna Martins, Lúcia
C.S. Aguiar, Heiddy M. Alvarez, L. Cardozo-Filho, Aline V.
Coelho and O.A.C. Antunes
The first palladium–catalyzed cross-coupling reaction
between arenediazonium tetrafluoroborate salts and chloroformates
to afford the corresponding substituted aryl carboxylic esters,
in the presence of catalytic amounts of Pd(OAc)2
is described.
[Back to top]
Synthesis and Transformation of Thiazolomorphinanedienes
Miklós Tóth, Zsuzsanna Gyulai, Sándor
Berényi and Attila Sipos
We here present a simple and efficient method for the
preparation of 2’-substituted-thiazolomorphinanedienes
3-5. A protocol is also presented for yielding
3-demethoxy-14β-hydroxy
derivatives of the thiazolomorphianedienes. The amino-, methyl-
and phenyl-substituents connected in these compounds in a
less rigid way to the “spacer” which offers the
opportunity to test the effect of this sterically more flexible
structure on the activity to opioid receptor subtypes.
[Back to top]
Vanadium-Substituted Keggin Type Heteropolyacid
are Used for the Selective Oxidation of Sulfides to Sulfoxides
and Sulfones Using Hydrogen Peroxide
G. Romanelli, D. Bennardi, V. Palermo, P. Vázquez
and P. Tundo
Various types of aromatic and aliphatic sulfides are
selectively oxidized to sulfoxides and sulfones with good
to excellent yields using H2O2
35% p/V in the presence of catalytic amounts of Keggin heteropolyacid
(H5PMo11Al0.5V0.5O40)
using acetonitrile as solvent.
[Back to top]
Excellent Exo/Endo-Selectivity in the 1,3-Dipolar
Cycloaddition of Cyclic Azomethine Ylide: Exploring the Facile
Investigation of Cocaine Antagonists
Joydev K. Laha
High exo-selectivity was achieved in the 1,3-dipolar
cycloaddition of a cyclic azomethine ylide and phenyl vinyl
sulfone or Opplozer’s camphorsultam chiral dipolarophile
leading to the synthesis of two novel tropane compounds.
[Back to top]
Total Synthesis of (±)-Euryfuran
Through Ti(III) Catalyzed Radical Cyclization
Antonio Rosales, Cristóbal López-Sánchez,
Míriam Alvarez Corral, Manuel Muñoz-Dorado and
Ignacio Rodríguez-García
A concise total synthesis of the furano-sesquiterpene
(±)-euryfuran, a bioactive metabolite from some marine
sponges, is presented. The key step is a highly diastereoselective
titanium (III) catalyzed radical cyclization of a farnesol
epoxyderivative.
[Back to top]
Enantiospecific Synthesis of (–)-Radicamine
B
Chunyan Liu, Junchao Gao, Guang Yang, Richard H. Wightman
and Shende Jiang
Radicamine B 2, the enantiomer of natural
radicamine B 5, was synthesized via a
chiral nitrone derived from D-xylose in 10 steps with an overall
yield of 15%.
[Back to top]
Synthesis of Multivalent Galactosides with High
Affinity for the Hepatic Asialoglycoprotein Receptor
Li Hai, Jiao Lu, Zhi-Rong Zhang, Shou-Zhu Liao, Jin-Cheng
Yang and Yong Wu
A series of bifunctional compounds carrying cluster thiogalactosides
L1-L6
as the cell targeting ligands were synthesized for gene delivery
to hepatocytes. Tetra-antennary dendr-OMs4
5 was used as a scaffold for the attachment of three galactosides,
while the other mesylate end was linked with cholesterol through
poly(ethylene glycol) chain with different length. This design
provided an effective entry for the synthesis of the bifunctional
compound with hepatocytes targeting ability.
[Back to top]
The Modular Synthesis of Chiral N-Heterocyclic
Carbene Precursors
Attila Paczal and András Kotschy
A series of chiral N-heterocyclic carbene precursors
based on the dihydroimidazole framework were prepared from
easily available chiral amines. The sequential attachment
of these amines and mesitylamine to chloroacetyl chloride
followed by reduction and subsequent ring closure gave the
desired dihydroimidazolium salts in good yield.
[Back to top]
The Novel One-Pot Synthesis of Functionalized
Vinyl Sulfides Using Triphenylphosphine Catalyzed Nucleophilic
Addition of Thiols to Acetylenes
Robabeh Baharfar, Seyed M. Baghbanian, Roghayeh Hossein
nia and Hamid R. Bijanzadeh
3-mercapto-2-butanone undergoes a smooth reaction with
electron-deficient symmetric and asymmetric acetylenes in
the presence of catalytic amount of triphenylphosphine under
neutral conditions to produce S-functionalized vinyl sulfides
(Z/E isomers) in moderately high yields.
[Back to top]
Enantioselective Alkynylation of Aromatic Aldehydes
Catalyzed by New C2-Symmetric
Bis-Schiff Base Amino Alcohol
Min Hong and Qi-dong You
Some novel C2-symmetric
bis-schiff base amino alcohols were prepared, the structure
of which is similar to Salens`. Butyl lithium was chosen as
the base to generate nucleophilic reagent in asymmetric addition
to benzaldehyde using amino alcohols as chiral ligand. Only
moderate enantioselectivity was observed, and by using the
ligand with inverted configuration, the resulting alcohol
has the inverted configuration.
[Back to top]
KF-Al2O3
Promoted Synthesis of Fully Substituted New Indeno and Naphtho-
Fused Thiophenes Under Solvent Free Conditions by Controlled
Microwave Heating
Firouz M. Moghaddam, Hamdollah Saeidian, Zohreh Mirjafary
and Azam sadeghi
KF-Al2O3
catalyzes the reaction of arylthioacetamides with α-bromo
ketones to give fully substituted new indeno- and naphtho-
fused thiophenes with good yields under solvent-free conditions
by controlled microwave heating. A mechanism is proposed for
the reaction course.
[Back to top]
N-Acylbenzotriazole Mediated Synthesis
of Some Methacrylamido Amino Acids
Deniz Hür, Sultan F. Ekti and Rdvan Say
N-acylbenzotriazole mediated synthetic methodology for
introducing methacryloyl (MA) group onto amino acids with
complete retention of chirality has been disclosed.
[Back to top]
A Facile Synthesis of Lipo-Chitopentaose Nodulation
Factor
G.-L. Huang and Kongliang Wong
We prepared the penta-N-acetyl-chitopentaose
2 by using recombinant Escherichia coli
(E. coli) strains harboring the nodC gene (encoding
chitooligosaccharide synthase) from Azorhizobium caulinodans.
The deacetylase NodB removed the N-acetyl moiety
from the nonreducing terminus of 2 to give
tetra-N-acetyl-chitopentaose 3.
N-Acylation of 3 with stearyl chloride was performed
in DMF containing water and provided the corresponding lipo-chitopentaose
nodulation factor 4.
[Back to top]
Aminocarbonylation of 2-Iodothiophene: High-Yielding
Synthesis of Thiophen-2-yl-glyoxylamides
Attila Takács, Andrea Petz, Balázs Jakab
and László Kollár
2-Iodothiophene has been aminocarbonylated with simple
unfunctionalised amines as well as with amino acid esters
as N-nucleophiles in the presence of palladium(0)
catalysts formed in situ from palladium(II) acetate
and triphenylphosphine. While at low carbon monoxide pressure
conversions of synthetic interest have been obtained with
simple amines only, at higher carbon monoxide pressure various
ketocarboxamides, formed via double carbon monoxide
insertion, have been isolated with good yields (up to 85%).
[Back to top]
Tris(2-Hydroxyphenyl)Methanes: Ligand with High
Affinity Toward a Chloride Anion
Tatsunori Sato, Shintaro Higuchi and Kazuaki Ito
Tris(2-hydroxyphenyl)methane derivatives (1)
displayed excellent selectivity for chloride (Cl-),
in comparison with bromide (Br-),
iodide (I-) and nitrate (NO3)
ions. This selectivity is attributed to the fit size and shape
of chloride, which favor the formation of a stable host-guest
complex through the multiple intermolecular hydrogen bonds
between 1 and the chloride anion.
[Back to top]
Synthesis and Antitumor Activities of 3-Substituted
1-(5 formylfurfuryl) indolin-2-one Derivatives
Fusheng Zhou, Jianbin Zheng, Xiaochun Dong, Zhiwen Zhang,
Lingling Zhao, Xianyi Sha, Lin Li and Ren Wen
Forty-two 3-substituted 1-(5-formylfurfuryl)indolin-2-ones
were synthesized and most of these compounds exhibited potent
inhibitory activities against P. oryzae (MIC = 0.78-25
µg/mL) and human intestinal Caco-2 cells (IC50
= 0.19-9.42 µM). Eight compounds selected for further
screening also showed inhibitory activities (IC50
= 1.84-10.32 µM) against human lung adenocarcinoma cells
(SPC-A1). |
