Md. Serajul Haque Faizi

Next generation NIR fluorophores for tumor imaging and fluorescence-guided surgery: A review

Cancer is a group of diseases responsible for the major causes of mortality and morbidity among people of all ages. Even though medical sciences have made enormous growth, complete treatment of this deadly disease is still a challenging task. Last few decades witnessed an impressive growth in the design and development of near infrared (NIR) fluorophores with and without recognition moieties for molecular recognitions, imaging and image guided surgeries. The present article reviews recently reported NIR emitting organic/inorganic fluorophores that targets and accumulates in organelle/organs specifically for molecular imaging of cancerous cells. Near infrared (NIR probe) with or without a tumor-targeting warhead have been considered and discussed for their applications in the field of cancer imaging. In addition, challenges persist in this area are also delineated in this review.

Crystal structure of 9,9′-{(1E,1′E)-[1,4-phenyl­enebis(aza­nylyl­idene)]bis­(methanylyl­idene)}bis­(2,3,6,7-tetra­hydro-1H,5H-pyrido[3,2,1-ij]quinolin-8-ol)

The whole molecule of the title compound is generated by inversion symmetry; the central benzene ring being situated about a crystallographic inversion center. The aromatic ring of the julolidine moiety is inclined to the central benzene ring by 33.70 (12)°, and the conformation about the C=N bonds is E. There are two intramolecular O—H⋯N hydrogen bonds in the molecule, generating S(6) ring motifs.

Crystal structure of di-μ-chlorido-bis(chlorido­{N1-phenyl-N4-[(pyridin-2-yl-κN)methyl­idene]benzene-1,4-di­amine-κN4}mercury(II))

The whole molecule of the title complex, [Hg2Cl4(C18H15N3)2], is generated by inversion symmetry. It was synthesized from the pyridine-derived Schiff base N-phenyl-N′-[(pyridin-2-yl)methylidene]benzene-1,4-diamine (PPMBD). The five-coordinated Hg2+ ions have a distorted square-pyramidal environment defined by two N atoms, viz. the imine and the other pyridyl [Hg—N = 2.467 (6) and 2.310 (6) Å, respectively] belonging to the bidentate iminopyridine ligand, and three Cl atoms [Hg—Cl = 2.407 (2), 2.447 (2) and 3.031 (2) Å]. The longest Hg—Cl bond is bridging about the inversion centre. In the ligand, the central ring and pyridine ring are oriented at a dihedral angle of 8.1 (4)°, while the planes of the pyridine ring and the terminal phenyl ring are oriented at a dihedral angle of 53.8 (4)°. In the crystal, molecules are linked by N—H⋯Cl and C—H⋯Cl hydrogen bonds, forming sheets parallel to (001).

Next Generation Antineoplastic Agents: A Review on Structurally Modified Vinblastine (VBL) Analogues

BACKGROUND Throughout the history of human civilizations, cancer has been a major health problem. Despite the advancements made by modern medical sciences, complete treatment or removal of cancerous cells is still a challenging task. Vinblastine, an alkaloid obtained from Catharanthus roseus (L.) G. Don is one of the prominent antineoplastic agents that is being clinically used. To improve the biological potential and reduce sideeffects of this structurally complex molecule, several related analogues have been reported. The present article reviews recently reported structurally modified vinblastine analogues and its impact on biological activity. METHODS We carried out a comprehensive database search on recently reported vinblastine analogues. Both upper (catharanthine) and lower (vindoline) structural units have been considered. The role of functional group modification on anticancer activities has been discussed. In addition, formulations based on vinblastine being considered by NIH, USA for different types of cancers have also been discussed. RESULTS Around fifty papers were included in the review, including computational and experimental ones. These papers were analysed to discuss the mechanism of action of the parent vinblastine molecule and their analogues. The importance of each functionalities on its anticancer activity have been discussed. This reviewed identified the potential sites of vinblastine core where modification led to improved anticancer activity. Furthermore, several new formulations have also been discussed which are under different phases of clinical trial. CONCLUSION The present article highlights the importance of vinblastine in cancer chemotherapy. Literature survey confirms that it is now possible to synthesize new molecules with activity in picomolar range. Not only the periphery of the molecule, the core structure of this magical molecule can be modified to achieve next generation antineoplastic agents.

Crystal structure of (E)-2-{[(4-anilinophen­yl)imino]meth­yl}-4-nitro­phenol

The title compound, C19H15N3O3, features an intramolecular O—H⋯N hydrogen bond and an E conformation for the Schiff base unit.

Crystal structure of (E)-9-({[4-(di­ethyl­amino)­phen­yl]imino}­meth­yl)-2,3,6,7-tetra­hydro-1H,5H-pyrido[3,2,1-ij]quinolin-8-ol

In the title compound, the hydroxy group forms a intramolecular hydrogen bond to the imine N atom and generates an S(6) ring motif. The conformation about the C=N bond is E, and the aromatic ring of the julolidine moiety is inclined to the benzene ring by 3.74 (14)°.

Crystal structure and DFT study of 2-(pyren-1-yl)-1H-benzimidazole

The title compound was prepared from an equimolar mixuture of o-phenylenediamine and pyrene-1-carboxaldehyde. We report herein on its crystal structure and a density functional theory (DFT) study.

Crystal structure of (E)-2,6-di-tert-butyl-4-{[2-(2,4-di­nitro­phen­yl)hydrazinylidene]meth­yl}phenol

The title compound was obtained from the condensation reaction of 3,5-di-tert-butyl-4-hydroxybenzaldehyde and 2,4-dinitrophenylhydrazine. The essential part (including all the non-hydrogen atoms except two methyl carbons) of the molecule lies on a mirror plane, which bisects the t-butyl groups.

Crystal structure and DFT study of (E)-2,6-di-tert-butyl-4-{[2-(pyridin-2-yl)hydrazin-1-yl­idene)meth­yl}phenol

The title Schiff base was synthesized via the condensation reaction of 3,5-di-tert-butyl-4-hydroxybenzaldehyde and 2-hydrazinylpyridine and crystallized with a single molecule in the asymmetric unit. The conformation about the C=N bond is E. In the crystal, N—H⋯N hydrogen bonds connect pairs of molecules into dimers. In addition, weak C—H⋯O hydrogen bonds and C—H⋯π interactions are observed.

Crystal structure of (E)-N1-[(anthracen-9-yl)methyl­idene]-N4-phenyl­benzene-1,4-di­amine

The asymmetric unit of the title Schiff base contains three independent but conformationally similar molecules that are linked in the crystal through intermolecular N—H⋯N hydrogen bonds and C—H⋯π interactions, forming chains lying parallel to the c-axis direction.