0000000000403058
AUTHOR
Marcello Rossi
Studies on the apoptotic activity of natural and synthetic retinoids: discovery of a new class of synthetic terphenyls that potently support cell growth and inhibit apoptosis in neuronal and HL-60 cells.
New terphenyl derivatives have been synthesized and tested for their effect on cell survival in serum-free cultures. These compounds protected HL60 cells from death and supported their growth with an activity higher than that of the natural 14-hydroxy-retro-retinol. Terphenyls 26 and 28 also possess antiapoptotic activity on neuronal cells, proving them as possible candidates for the treatment of neurodegenerative and ischemic diseases.
Effects of two-carbon bridge region methoxylation of benztropine: discovery of novel chiral ligands for the dopamine transporter
6-Methoxylated and 8-oxygenated benztropines were prepared and evaluated for their DAT and SERT activity (binding and uptake inhibition). Methoxylation at the two-carbon bridge of benztropine produced a novel class of potent and selective DAT ligands. An interesting enantioselectivity was also observed for this new class of chiral benztropines. The inactivity of the 8-oxygenated analogues seems to point out that, unlike cocaine and its analogues, interactions of benztropine ligands with DAT may be strongly governed by the nitrogen atom.
Programmed cell death (PCD) associated with the stilbene motif of arotinoids: discovery of novel apoptosis inducer agents possessing activity on multidrug resistant tumor cells
Considering that the stereochemistry of the C9-C10 alkenyl portion of natural 9-cis-RA, as the one of the olefinic moiety of the previously described isoxazole retinoid 4, seems of particular importance for their apoptotic activity, we prepared a novel class of TTNPB analogues bearing both the cis or trans configuration of the alkenyl portion. The compounds were evaluated in vitro for their cytotoxic and apoptotic activities. We discovered that the cis-TTNPB 9c possesses apoptotic activity comparable with that of the retinoid 4. Moreover, the amino arotinoid 16c showed potent apoptotic activity in HL60 promyelocytic leukemia cells. Interestingly, 16c proved to be a particularly potent apopt…
Synthesis and pharmacology of 6-substituted benztropines: discovery of novel dopamine uptake inhibitors possessing low binding affinity to the dopamine transporter
A series of 6alpha- and 6beta-substituted benztropines were synthesized. A marked enantioselectivity was observed for the 6beta-methoxylated benztropines, the (1R)-isomers being more potent than the corresponding (1S) compounds. The racemic 6alpha-methoxy-3-(4',4' '-difluorodiphenylmethoxy)tropane (5 g) was the most potent compound. It has been found that modifications at the 6-position of benztropine might reduce the DAT binding affinity, maintaining otherwise a significant dopamine uptake inhibitory activity. A reinvestigation of the absolute configuration of 6beta-methoxytropinone proved the 6R configuration for the (+)-enantiomer.
Retinoid acid and analogs as potent inducers of differentiation and apoptosis. New promising chemopreventive and chemotherapeutic agents in oncology
Abstract In this report we will describe the preparation and the biological activity of a novel class of heterocyclic arotinoids endowed with potent cytotoxic and apoptotic acitivity. Structureactivity relationship studies revealed that the different stereochemistry at the C9 double bond of retinoids seems associated with a different biological activity: potent apoptotic activity for the cis-isomers, whereas differentiating activity for the trans structures. An interesting modified Wittig procedure that allows easily to arotinoids will also be described. The substitution of the alkenyl portion with a more flexible oxymethyl or aminomethyl moiety gave compounds with poor activity, whereas i…
Heterocycle-containing retinoids. Discovery of a novel isoxazole arotinoid possessing potent apoptotic activity in multidrug and drug-induced apoptosis-resistant cells.
In a search for retinoic acid (RA) receptor ligands endowed with potent apoptotic activity, a series of novel arotinoids were prepared. Because the stereochemistry of the C9-alkenyl portion of natural 9-cis-RA and the olefinic moiety of the previously synthesized isoxazole retinoid 4 seems to have particular importance for their apoptotic activity, novel retinoid analogues with a restricted or, vice versa, a larger flexibility in this region were designed and prepared. The new compounds were evaluated in vitro for their ability to activate natural retinoid receptors and for their differentiation-inducing activity. Cytotoxic and apoptotic activities were, in addition, evaluated. In general, …
Heterocyclic and Phenyl Double-Bond-Locked Combretastatin Analogues Possessing Potent Apoptosis-inducing activity in HL60 and in MDR Cell lines
Two new series of combretastatin (CA-4) analogues have been prepared. The alkenyl motif of CA-4 was replaced either by a five-membered heterocyclic (isoxazoline or isoxazole) or by a six-membered ring (pyridine or benzene). The new compounds have been evaluated for their effects on tubulin assembly and for cytotoxic and apoptotic activities. Five compounds (18b, 20a, 21a, 34b, and 35b) demonstrated an attractive profile of cytotoxicity (IC501 microM) and apoptosis-inducing activity but poor antitubulin activity. The isoxazoline derivatives 18b, 20a, and 21a, demonstrated potent apoptotic activity different from that of natural CA-4. Their ability to block most cells in the G2 phase suggests…
A convenient synthesis of unsymmetrically substituted terphenyls of biologically active stilbenes via a double Suzuki cross-coupling protocol
A double Suzuki cross-coupling protocol has been devised as a practical route to a variety of terphenyls. Good chemoselectivity was observed. Unsymmetrically substituted triphenylenes were also easily prepared.