- Design and synthesis of a new series of 3,5-disubstituted-1,2,4-oxadiazoles as potential colchicine binding site inhibitors: Antiproliferative activity, molecular docking, and SAR studies
-
The development of anticancer compounds targeting the colchicine-binding site of tubulin, termed colchicine-binding site inhibitors (CBSIs) is a promising research area for pharmaceutical companies and research institutes. A series of 3,5-disubstituted 1,
- Abdel-Aal, Eatedal H.,Abdel-Sami, Zakaria K.,Abo-Dya, Nader E.,Al-Karmalawy, Ahmed A.,Diab, Rana T.
-
p. 21657 - 21669
(2021/12/09)
-
- N-Acylbenzotriazole: convenient approach for protecting group-free monoacylation of symmetric diamines
-
Abstract: An efficient green route for monoacylation of aromatic diamines, namely o-phenylenediamine and p-phenylenediamine and aliphatic diamines ethylenediamine and piperazine using N-acylbenzotriazoles (NABs) in n-butanol was developed. The new protocol does not require prior selective protection of the diamine and comprises simple conditions, short reaction times, an easy work up as well as high isolated yields (69–94%). Moreover, the method described herein enable stepwise acylation of aliphatic diamines such as ethylenediamine and piperazine with two different N-acylbenzotriazoles affording unsymmetrical substituted diamines that can be used for construction of pharmaceutically important targets such as drugs, foldamers, and drug conjugates. Graphic abstract: [Figure not available: see fulltext.]
- Agha, Khalid A.,Abo-Dya, Nader E.,Ibrahim, Tarek S.,Abdel-Aal, Eatedal H.,Abdel-Samii, Zakaria K.
-
p. 589 - 598
(2020/05/06)
-
- Chemical modification of oximes with N-protected amino acids
-
The modification of oximes, including 5α-steroids, with N-protected amino acids, in solution phase, using benzotriazole methodology is reported.
- Barbakadze, Nana N.,Jones, Rachel A.,Rosario, Nicole Rivera,Nadaraia, Nanuli Sh,Kakhabrishvili, Meri L.,Dennis Hall,Katritzky, Alan R.
-
p. 7181 - 7184
(2015/02/19)
-
- Synthesis and antibacterial evaluation of amino acid-antibiotic conjugates
-
Amino acid conjugates of quinolone, metronidazole and sulfadiazine antibiotics were synthesized in good yields using benzotriazole methodology. All the conjugates were screened for their antibacterial activity using methods adapted from the Clinical and L
- Ibrahim, Mohamed A.,Panda, Siva S.,Birs, Antoinette S.,Serrano, Juan C.,Gonzalez, Claudio F.,Alamry, Khalid A.,Katritzky, Alan R.
-
p. 1856 - 1861
(2014/04/17)
-
- Gabapentin hybrid peptides and bioconjugates
-
Synthetic approaches to gabapentin bioconjugates that overcome the tendency of gabapentin to cyclize into its γ-lactam are studied. Gabapentin was converted by N-acylation at its N-terminus into di-, tri-, and tetrapeptides (L-Ala-Gbp, L-Val-Gbp, L-Ala-L-Phe-Gbp, Gly-L-Ala-β-Ala-Gbp). Carboxyl-activated Boc-protected gabapentin was used to N-, O-, and S-acylate small peptides and hormones to give conjugates that could also provide prodrugs containing conformationally constrained gabapentin units.
- Lebedyeva, Iryna O.,Ostrov, David A.,Neubert, John,Steel, Peter J.,Patel, Kunal,Sileno, Sean M.,Goncalves, Kevin,Ibrahim, Mohamed A.,Alamry, Khalid A.,Katritzky, Alan R.
-
supporting information
p. 1479 - 1486
(2014/03/21)
-
- Non-phosgene route to unsymmetrical ureas from N-Cbz-α-amino acid amides
-
A convenient method toward the synthesis of α-amino acid-derived unsymmetrical ureas 2 is described herein. This route involves an interesting rearrangement of amides of N-Cbz-α-amino acids 1, which presumably entails the intermediacy of hydantoins that is followed by hydrolysis to afford unsymmetrical ureas 2 in quantitative yields and high purity.
- Ghazvini Zadeh, Ebrahim H.,Abo-Dya, Nader E.,Sotuyo, Ania C.,Ghiviriga, Ion,Hall, C. Dennis
-
p. 5467 - 5469
(2013/09/23)
-
- Green, catalyst-free synthesis of mesalazine conjugates
-
A greener protocol for the synthesis of mesalazine conjugates is reported. Mesalazine conjugates are prepared in high yields by a one-pot reaction of mesalazine and aminoacyl/peptidoylbenzotriazoles in water under microwave irradiation. Georg Thieme Verlag Stuttgart New York.
- Ibrahim, Mohamed A.,Panda, Siva S.,Alamry, Khalid A.,Katritzky, Alan R.
-
p. 3255 - 3258
(2013/12/04)
-
- Synthesis and antimalarial bioassay of quinine - peptide conjugates
-
Amino acid and peptide conjugates of quinine were synthesized using microwave irradiation in 52-95% yields using benzotriazole methodology. The majority of these conjugates retain in vitro antimalarial activity with IC50 values below 100 nm, similar to quinine.
- Panda, Siva S.,Ibrahim, Mohamed A.,Kuecuekbay, Hasan,Meyers, Marvin J.,Sverdrup, Francis M.,El-Feky, Said A.,Katritzky, Alan R.
-
p. 361 - 366
(2013/10/08)
-
- A new benzotriazole-mediated stereoflexible gateway to hetero-2,5- diketopiperazines
-
Open chain Cbz-L-aa1-L-Pro-Bt (Bt=benzotriazole) sequences were converted into either the corresponding trans- or cis-fused 2,5- diketopiperazines (DKPs) depending on the reaction conditions. Thermodynamic tandem cyclization/epimerization afforded selectively the corresponding trans-DKPs (69-75%). Complementarily, tandem deprotection/cyclization led to the cis-DKPs (65-72%). A representative set of proline-containing cis- and trans-DKPs has been prepared. A mechanistic investigation, based on chiral HPLC, kinetics, and computational studies enabled a rationalization of the results. Stereoflexible route to DKPs: A convenient, versatile, and flexible benzotriazole-mediated methodology for the synthesis of proline-containing hetero-2,5-diketopiperazines (DKPs) is reported. Depending on the reaction conditions, either cis- or trans-configured DKPs were obtained starting from the same inexpensive l,l-dipeptidoyl benzotriazole key intermediate (see scheme). Kinetics, chiral HPLC, and computational studies forged a background for mechanistic rationalization. Copyright
- Monbaliu, Jean-Christophe M.,Hansen, Finn K.,Beagle, Lucas K.,Panzner, Matthew J.,Steel, Peter J.,Todadze, Ekaterina,Stevens, Christian V.,Katritzky, Alan R.
-
supporting information; experimental part
p. 2632 - 2638
(2012/04/17)
-
- Triphenylphosphoranylidene substituted heterocycles as versatile intermediates
-
N-Cbz-(α-aminoacyl)benzotriazoles 5a-e reacted with (stabilized-methylene)triphenylphosphoranes 6 and 13 to give the corresponding esters 7a-e (66-91%) or nitriles 14a-e (63-85%). Deprotection of N-Cbz-γ-amino-β-oxo-α-triphenylphosphoranylidene esters 7a-
- Katritzky, Alan R.,Vincek, Adam S.,Steel, Peter J.
-
experimental part
p. 1401 - 1423
(2009/07/17)
-