T3P® (propylphosphonic anhydride) mediated conversion of carboxylic acids into acid azides and one-pot synthesis of ureidopeptides

Prodrugs for nitroreductase based cancer therapy-4: Towards prostate cancer targeting: Synthesis of N-heterocyclic nitro prodrugs, Ssap-NtrB enzymatic activation and anticancer evaluation

In this study, various N-heterocyclic nitro prodrugs (NHN1-16) containing pyrimidine, triazine and piperazine rings were designed and synthesized. The final compounds were identified using FT-IR, ¹H NMR, ¹³C NMR as well as elemental analyses. Enzymatic activities of compounds were conducted by using HPLC analysis to investigate the interaction of substrates with Ssap-NtrB nitroreductase enzyme. MTT assay was performed to evaluate the toxic effect of compounds against Hep3B and PC3 cancer cell lines and healthy HUVEC cell. It was observed that synthesized compounds NHN1-16 exhibited different cytotoxic profiles. Pyrimidine derivative NHN3 and triazine derivative NHN5 can be good drug candidates for prostate cancer with IC₅₀ values of 54.75 µM and 48.9 µM, respectively. Compounds NHN6, NHN10, NHN12, NHN14 and NHN16 were selected as prodrug candidates because of non-toxic properties against three different cell models. The NHN prodrugs and Ssap-NtrB combinations were applied to SRB assay to reveal the prodrug capabilities of these selected compounds. SRB screening results showed that the metabolites of all selected non-toxic compounds showed remarkable cytotoxicity with IC₅₀ values in the range of 1.71-4.72 nM on prostate cancer. Among the tested compounds, especially piperazine derivatives NHN12 and NHN14 showed significant toxic effect with IC₅₀ values of 1.75 nM and 1.79 nM against PC3 cell compared with standart prodrug CB1954 (IC₅₀: 1.71 nM). Novel compounds NHN12 and NHN14 can be considered as promising prodrug candidates for nitroreductase-prodrug based prostate cancer therapy.

Palladium-Catalyzed Synthesis of Aldehydes from Aryl Iodides and Formic acid with Propylphosphonic Anhydride as the Activator

An interesting palladium-catalyzed carbonylative procedure for the synthesis of aromatic aldehydes from aryl iodides has been developed. By using propylphosphonic anhydride as the activator for formic acid, moderate to good yields of the corresponding aldehydes were produced with formic acid as the carbonyl and hydrogen donors. Interestingly, neither additional phosphine ligand nor inert gas protection is needed here.

Synthesis of new steroidal imidazo [1,2-a] pyridines: DNA binding studies, cleavage activity and in vitro cytotoxicity

A one-pot strategy for the catalytic synthesis of series of new 5α-cholestan-6-spiro-5'-phenylamino-2H-imidazo [1',2'-a] pyridines (4-14) has been investigated. The synthesized products were obtained in good yields (85-90%) and the protocol uses Multi-component Reaction (MCR) involving steroidal ketones, 2-aminopyridines, isocyanides and propylphosphonic anhydride (®T3P) as a catalyst. After characterization by spectral and analytical data, the interaction studies of compounds (4-6) with DNA were studied by UV-vis, fluorescence spectroscopy, gel electrophoresis and molecular docking. The compounds bind to DNA preferentially through electrostatic and hydrophobic interactions with Kb; 2.35×10(4), 3.71×10(4) and 3.24×10(4) M(-1), respectively, indicating the higher binding affinity of compound 5 towards DNA. Gel electrophoresis showed the concentration dependent cleavage activity of compounds 4-6 with DNA. Molecular docking studies suggested that compounds bind through minor groove to DNA. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay depicted promising anti-proliferative activity of compound 4-9 against different given cancer cells. In Western blotting, the expressions of relevant apoptotic markers depicted an apoptosis by steroidal imidazopyridines in A549 cells. Annexin V-FITC/PI staining data indicated that compounds could effectively induce apoptosis in A549 cells in a dose-dependent manner. FACS analysis shows that the compound 6 bring about cell cycle arrest at 2.62 μM concentration.

Disodium Salt of 2-(5-phenyl-1, 3, 4-oxadiazol-2-yl) Phenyl Phosphate as a Fluorescent Probe for Determination of ALP

A convenient method to synthesize disodium salt of 2-(5-phenyl-1, 3, 4-oxadiazol-2-yl) phenyl phosphate (OXDP), a substrate for the fluorescent determination of alkaline phosphatase (ALP) activity, via an one-pot procedure of condensation between the benzoic acid and 2-hydroxybenzhydrazide at triethylamine alkaline solution in the presence of propylphosphonic anhydride, was realized. Preliminary tests reveal that the lessened fluorescence intensity resulting from enzyme reaction is proportional to ALP activity in the range of 1.0-25.0 U/L with the detection limit of 0.25U/L, which can be successfully applied to assess ALP in human serum with good precision.