820239-42-7Relevant academic research and scientific papers
Towards the biodegradation pathway of fosfomycin
Pallitsch,Schweifer,Roller,Hammerschmidt
, p. 3276 - 3285 (2017/04/21)
Three functionalised propylphosphonic acids were synthesised to study C-P bond cleavage in R. huakuii PMY1. (R)-1-Hydroxy-2-oxopropylphosphonic acid [(R)-5] was prepared by chiral resolution of (±)-dimethyl 1-hydroxy-2-methylallyllphosphonate [(±)-12], followed by ozonolysis and deprotection. The N-(l-alanyl)-substituted (1R,2R)-2-amino-1-hydroxypropylphosphonic acid 10, a potential precursor for 2-oxopropylphosphonic acid (5) in cells, was obtained by coupling the aminophosphonic acid with benzotriazole-activated Z-l-alanine and hydrogenolytic deprotection. (1R*,2R*)-1,2-Dihydroxy-3,3,3-trifluoropropylphosphonic acid, a potential inhibitor of C-P bond cleavage after conversion into its 2-oxo derivative in the cell, was accessed from trifluoroacetaldehyde hydrate via hydroxypropanenitrile 21, which was silylated and reduced to the aldehyde (±)-23. Diastereoselective addition of diethyl trimethylsilyl phosphite furnished diastereomeric α-siloxyphosphonates. The less polar one was converted to the desired racemic phosphonic acid (±)-(1R*,2R*)-9 as its ammonium salt.
Synthesis, molecular docking and anticancer studies of peptides and iso-peptides
Jabeen, Farukh,Panda, Siva S.,Kondratyuk, Tamara P.,Park, Eun-Jung,Pezzuto, John M.,Ihsan-Ul-Haq,Hall, C. Dennis,Katritzky, Alan R.
supporting information, p. 2980 - 2984 (2015/06/22)
Chiral peptides and iso-peptides were synthesized in excellent yield by using benzotriazole mediated solution phase synthesis. Benzotriazole acted both as activating and leaving group, eliminating frequent use of protection and subsequent deprotection. The procedure was based on the hypothesis that epimerization should be suppressed in solution due to a faster coupling rate than SPPS. All the synthesized peptides complied with Lipinski's Ro5 except for the rotatable bonds. Inhibition of cell proliferation of cancer cell lines is one of the most commonly used methods to study the effectiveness of any anticancer agents. Synthesized peptides and iso-peptides were tested against three cancer cell lines (MCF-7, MDA-MB 231) to determine their anti-proliferative potential. NFkB was also determined. Molecular docking studies were also carried out to complement the experimental results.
Chemical modification of oximes with N-protected amino acids
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)
The modification of oximes, including 5α-steroids, with N-protected amino acids, in solution phase, using benzotriazole methodology is reported.
Gabapentin hybrid peptides and bioconjugates
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)
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.
Synthesis and antibacterial evaluation of amino acid-antibiotic conjugates
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)
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
Green, catalyst-free synthesis of mesalazine conjugates
Ibrahim, Mohamed A.,Panda, Siva S.,Alamry, Khalid A.,Katritzky, Alan R.
, p. 3255 - 3258 (2013/12/04)
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.
Synthesis and antimalarial bioassay of quinine - peptide conjugates
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)
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.
Traceless chemical ligations from O-acyl serine sites
El Khatib, Mirna,Elagawany, Mohamed,Jabeen, Farukh,Todadze, Ekaterina,Bol'Shakov, Oleg,Oliferenko, Alexander,Khelashvili, Levan,El-Feky, Said A.,Asiri, Abdullah,Katritzky, Alan R.
supporting information; experimental part, p. 4836 - 4838 (2012/07/28)
Chemical ligation via O- to N-acyl transfer of O-acylated serine containing peptides affords serine containing native peptides via 8- and 11-membered cyclic transition states opening the door to a wide variety of potential applications to peptide elaborat
A new benzotriazole-mediated stereoflexible gateway to hetero-2,5- diketopiperazines
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)
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
Chemical ligation of S-scylated cysteine peptides to form native peptides via 5-, 11-, and 14-membered cyclic transition states
Katritzky, Alan R.,Tala, Srinivasa R.,Abo-Dya, Nader E.,Ibrahim, Tarek S.,El-Feky, Said A.,Gyanda, Kapil,Pandya, Keyur M.
experimental part, p. 85 - 96 (2011/04/12)
Cysteine-containing dipeptides 3a-l, (3b+3b′) (compound numbers in parentheses are used to indicate racemic mixtures; thus (3b+3b′) is the racemate of 3b and 3b′), and tripeptide 13 were synthesized in 68-96% yields by acylation of cysteine with N-(Pg-α-aminoacyl)- and N-(Pg-α-dipeptidoyl)benzotriazoles (where Pg stands for protecting group in the nomenclature for peptides throughout the paper) in the presence of Et3N. Cysteine-containing peptides 3a-l and 13 were S-acylated to give S-(Pg-α-aminoacyl)dipeptides 5a-l and S-(Pg-α-aminoacyl) tripeptide 14 without racemization in 47-90% yields using N-(Pg-α- aminoacyl)benzotriazoles 2 in CH3CN-H2O (7:3) in the presence of KHCO3. (In our peptide nomenclature, the prefixes di-, tri-, etc. refer to the number of amino acid residues in the main peptide chain; amino acid residues attached to sulfur are designated as S-acyl peptides. Thus we avoid use of the prefix "iso".) Selective S-acylations of serine peptide 3k and threonine peptide 3l containing free OH groups were thus achieved in 58% and 72% yield, respectively. S-(Pg-α-aminoacyl)cysteines 4a,b underwent native chemical ligations to form native dipeptides 3f,i via 5-membered cyclic transition states. Microwave irradiation of S-(Pg-α-aminoacyl)tripeptide 15 and S-(Pg-α-aminoacyl)tetrapeptide 17 in the presence of NaH2PO4/Na2HPO 4 buffer solution at pH 7.8 achieved chemical ligations, involving intramolecular migrations of acyl groups, via 11- and 14-membered cyclic transition states from the S-atom of a cysteine residue to a peptide terminal amino group to form native peptides 19 and 20 in isolated yields of 26% and 23%, respectively.
