Discovery of N-pyridoyl-Δ2 -pyrazolines as Hsp90 inhibitors.

Hsp90, as a key molecular chaperone, plays an important role in modulating the activity of many cell signaling proteins and is an attractive target for anticancer therapeutics. Herein, we report the discovery of N-pyridoyl-Δ2 -pyrazoline analogs as novel Hsp90 inhibitors by integrated approaches of drug design, organic synthesis, cell biology, and qualitative proteomic analysis. Novel chemical compounds were designed and optimized in the adenosine triphosphate-binding site of Hsp90; lead optimized compounds were found to have significant interactions with Asp93 and other amino acids crucial for Hsp90 inhibition. The designed compounds were synthesized by a two-step procedure; different aromatic aldehydes were reacted with various acetophenones to form substituted 1,3-diphenyl-prop-2-enones (Ic-Io), which upon reaction with isonicotinic acid hydrazide in the presence of glacial acetic acid form N-pyridoyl-Δ2 -pyrazoline compounds (PY1-PY13). Compounds PY3, PY2, and PY1 were identified as potential leads amongst the series, with promising anticancer activity against human breast cancer and melanoma cells, and the ability to inhibit Hsp90 similar to radicicol by drug-affinity responsive target stability proteomic analysis in a whole-cell assay.

Dual or multi-targeting inhibitors: The next generation anticancer agents.

Dual-targeting/Multi-targeting of oncoproteins by a single drug molecule represents an efficient, logical and alternative approach to drug combinations. An increasing interest in this approach is indicated by a steady upsurge in the number of articles on targeting dual/multi proteins published in the last 5 years. Combining different inhibitors that destiny specific single target is the standard treatment for cancer. A new generation of dual or multi-targeting drugs is emerging, where a single chemical entity can act on multiple molecular targets. Dual/Multi-targeting agents are beneficial for solving limited efficiencies, poor safety and resistant profiles of an individual target. Designing dual/multi-target inhibitors with predefined biological profiles present a challenge. The latest advances in bioinformatic tools and the availability of detailed structural information of target proteins have shown a way of discovering multi-targeting molecules. This neoteric artifice that amalgamates the molecular docking of small molecules with protein-based common pharmacophore to design multi-targeting inhibitors is gaining great importance in anticancer drug discovery. Current review focus on the discoveries of dual targeting agents in cancer therapy using rational, computational, proteomic, bioinformatics and polypharmacological approach that enables the discovery and rational design of effective and safe multi-target anticancer agents.