N-acyl-3,5-bis(arylidene)-4-piperidones and related compounds which stimulate fyn kinase

Discovery and Investigation of 1-[4-(2-Aminoethoxy)Phenylcarbonyl]- 3,5-Bis-(Benzylidene)-4-Piperidones as Candidate Antineoplastic Agents: Our Last 15 Years Study

This review outlines the discovery and development of a novel series of 1-[4-2- aminoethoxy)phenylcarbonyl]-3,5-bis-(benzylidene)-4-piperidones (5-8) as potential drug candidates over the last 15 years in our laboratory. Many of these compounds demonstrate excellent cytotoxic properties and are often more potent than contemporary anticancer drugs. Two highly important features of many of these molecules are first, the greater tumour-selective toxicity and second, the ability of these molecules to act as modulators of multi-drug resistance. The modes of action of some of the potent compounds are by apoptosis induction, generation of reactive oxygen species, activation of certain caspases and affecting mitochondrial functions. These molecules also display promising antimalarial and antimycobacterial properties. In a short term toxicity study, these molecules are well tolerated in mice. Structure-activity relationships and a drug delivery system along with pharmacokinetic studies and metabolic stability of these compounds, have been presented. The positive characteristics associated with the series (5-8) warrant their further evaluations as candidate antineoplastic drug candidates.

Curcumin analogues as possible anti-proliferative & anti-inflammatory agents

A series of novel curcumin analogues has been designed, synthesized and tested in vitro/in vivo as potential multi-target agents. Their anti-proliferative and anti-inflammatory activities were studied. Compounds 1b and 2b were stronger inhibitors of soybean lipoxygenase (LOX) than curcumin. Analogue 1b was also the most potent aldose reductase (ALR2) inhibitor. Two compounds, (1a and 1f) exhibited in vivo anti-inflammatory activity comparable to that of indomethacin, whereas derivative 1i exhibited even higher activity. The derivatives were also tested for their anti-proliferative activity using three different human cancer cell lines. Compounds 1a, 1b, 1d and 2b exhibited significant growth inhibitory activity as compared to curcumin, against all three cancer cell lines. Lipophilicity was determined as R(M) values using RPTLC and theoretically. The results are discussed in terms of the structural characteristics of the compounds. Docking simulations were performed on LOX and ALR2 inhibitor 1b and curcumin. Compound 1b is well fitted in the active site of ALR2, binding to the ALR2 enzyme in a similar way to curcumin. Allosteric interactions may govern the LOX-inhibitor binding.

Design, synthesis and bioevaluation of novel maleamic amino acid ester conjugates of 3,5-bisarylmethylene-4-piperidones as cytostatic agents

A novel series of maleamic amino acid ester conjugates of 3,5-bisarylmethylene-4-piperidones were prepared to investigate the efficacy of micronutrient conjugation in enhancing cytotoxic potency by improving selectivity and delivery. These compounds, prepared as anticancer agents, were expected to demonstrate enhanced selectivity towards malignant cells through the inhibition of topoisomerase IIalpha via protein thiolation. The cytostatic effects of these compounds were evaluated against three cell lines, namely murine L1210 leukemia cells, human Molt 4/C8 and CEM T-lymphocyte cells. All compounds were found to have greater potency than the reference drug melphalan. Several compounds were found to potently inhibit topoisomerase IIalpha and displayed cytostatic activity in the nanomolar range.

1,5-diaryl-3-oxo-1,4-pentadienes: a case for antineoplastics with multiple targets

A number of organic molecules which contain the 1,5-diaryl-3-oxo-1,4-pentadienyl group, referred to hereafter as the dienone moiety, have antineoplastic properties. Emphasis is made on the attachment of this structural moiety to several molecular scaffolds, namely piperidines, N-acylpiperidines, cycloalkanes and 3,4-dihydro-1H-napthalenes. Many of these compounds are potent cytotoxins having micromolar and nanomolar IC(50) values towards a wide range of neoplastic and transformed cells. On occasions, greater toxicity towards neoplasms than normal cells has been demonstrated. A number of these compounds have in vivo anticancer properties and in general excellent tolerability in rodents is demonstrated. The way in which a number of physicochemical properties such as redox potentials, torsion angles, atomic charges and logP values govern cytotoxic potencies are presented. The importance of the shapes of different compounds as determined by molecular modeling in contributing to antineoplastic properties is outlined. Arguments are presented in favour of designing antineoplastics which have multiple sites of action in contrast to those bioactive molecules which have only one molecular target. A number of compounds which possess the dienone group have different modes of action some of which are chronicled in this review, such as inducing apoptosis, affecting respiration in mitochondria, inhibiting macromolecular biosynthesis and both inhibiting and stimulating certain enzymes. Other important properties of these compounds are discussed including their anti-angiogenic, MDR-revertant and antioxidant properties. It is hoped that this eulogy of the importance of the dienone group will encourage researchers to consider incorporating this structural unit into candidate cytotoxins in the future.