1. N'-Benzoyl-5-methyl-1,3-diphenyl-1H-pyrazole-4-carbohydrazide
Chandra, N Srikantamurthy, Shamantha Kumar, B H Doreswamy, K B Umesha, M Mahendra Acta Crystallogr Sect E Struct Rep Online. 2013 Nov 13;69(Pt 12):o1769. doi: 10.1107/S1600536813029528.
In the title compound, C24H20N4O2, the pyrazole ring makes dihedral angles of 47.57 (10)° and 30.56 (11)° with its N-bound and C-bound phenyl groups, respectively. The C-N-N-C group that links the two carbonyls has a torsion angle of 81.5 (2)°. The torsion angles between the carbonyl groups and their adjacent pyrazole and phenyl rings are 125.89 (19) and 164.22 (17)°, respectively. In the crystal, pairs of mol-ecules are linked by N-H⋯O hydrogen bonds into R 2 (2)(10) ring motifs, which in turn link to form chains that propagate parallel to the c-axis direction.
3. Fluorescent and Photosensitizing Conjugates of Cell-Penetrating Peptide TAT(47-57): Design, Microwave-Assisted Synthesis at 60 °C, and Properties
Nancy M Okuda-Shinagawa, Yulia E Moskalenko, Helena C Junqueira, Maurício S Baptista, Carlos M Marques, M Terêsa Machini ACS Omega. 2017 Nov 30;2(11):8156-8166. doi: 10.1021/acsomega.7b01127. Epub 2017 Nov 20.
Conjugates based on cell-penetrating peptides (CPPs) are scientifically relevant owing to their structural complexity; their ability to enter cells and deliver drugs, labels, antioxidants, bioactive compounds, or DNA fragments; and, consequently, their potential for application in research and biomedicine. In this study, carboxyamidated fluorescently labeled conjugates FAM-GG-TAT(47-57)-NH2 and FAM-PEG6-TAT(47-57)-NH2 and photosensitizer-labeled conjugate Chk-PEG6-TAT(47-57)-NH2 [where TAT(47-57) is the CPP, 5(6)-carboxyfluorescein is the (FAM) fluorophore, chlorin k (Chk) is the photosensitizer, and the dipeptide glycyl-glycine (GG) or hexaethylene glycol (PEG6) is the spacer] were originally designed, prepared, and fully characterized. Practically, all chemical reactions of the synthetic steps (peptide synthesis, spacer incorporation, and conjugation) were microwave-assisted at 60 °C using optimized protocols to give satisfying yields and high-quality products. Detailed analyses of the conjugates using spectrofluorimetry and singlet oxygen detection showed that they display photophysical properties typical of FAM or Chk. Anticandidal activity assays showed that not only this basic property of TAT(47-57) was preserved in the conjugates but also that the minimal inhibitory concentration was slightly reduced for cells incubated with PS-bearing conjugate Chk-PEG6-TAT(47-57)-NH2. Overall, these results indicated that the synthetic approach on-resin assisted by microwaves at 60 °C is simple, straightforward, selective, metal-free, sufficiently fast, cleaner, and more cost-effective than those previously used for preparing this type of macromolecule. Furthermore, such new data show that microwaves at 60 °C and/or conjugation did not harm the integrity of the conjugates' constituents. Therefore, FAM-GG-TAT(47-57)-NH2, FAM-PEG6-TAT(47-57)-NH2, and Chk-PEG6-TAT(47-57)-NH2 have high potential for practical applications in biochemistry, biophysics, and therapeutics.
