Homospisulosine induced apoptosis in cervical carcinoma cells is associated with phosphorylation of Bcl-2 and up-regulation of p27/Kip1.

Spisulosine (1-deoxysphinganine) is a sphingoid amino alcohol isolated from the sea clams that showed potent antiproliferative activity against a broad spectrum of solid tumors but failed in clinical trials due to neurotoxicity. However, its structural similarity to other bioactive sphingoids, interesting mode of action, and appreciable potency against cancer cells make it a suitable lead for future anticancer drug development. The present study was conducted to elucidate mechanisms of the antiproliferative/cytotoxic effects of newly synthesized spisulosine analog homospisulosine (KP7). The evaluation was performed on cervical carcinoma cells, representing an in vitro model of one of the most common cancer types and a significant worldwide cause of women's cancer mortality. Treatment with homospisulosine (2.0 µM) for 24, 48, and 72 h significantly inhibited the growth of HeLa cells in vitro and induced apoptosis detectable by DNA fragmentation, externalization of phosphatidylserine, dissipation of mitochondrial membrane potential, activation of caspase-3 and cleavage of PARP. In addition, treating HeLa cells with spisulosine increased p27 and Bcl-2 on protein levels and phosphorylation of Bcl-2 on Ser70 residue. These results support the potential for spisulosine analogs represented here by homospisulosine for future therapeutic development.

The convergent synthesis and anticancer activity of broussonetinines related analogues.

The convergent synthesis of broussonetinines related congeners 3 and 4 with the simple C13 alkyl side chain and differently configured pyrrolidine skeleton has been achieved. Our approach relied on the [3,3]-sigmatropic rearrangements of chiral allylic substrates derived from d-xylose. Cross metathesis of the common oxazolidinone intermediates 7 and 8 with tridec-1-ene followed by alkylative cyclization completed the construction of both C-alkyl iminosugars. The targeted compounds 3 and 4 were screened for antiproliferative/cytotoxic activities against multiple cancer cell lines by MTT assay. Compound 3 exhibited very good in vitro potency on Caco-2 and Jurkat cell lines with IC50 value of 5.1 µM and 5.8 µM, respectively.

Total synthesis and antiproliferative/cytotoxic profiling of 2-epi-jaspine B.

A straightforward access to 2-epi-jaspine B (4.HCl) has been developed. Key to the approach was the use of Overman rearrangement for the instalment of a stereocentre bearing a nitrogen atom. Subsequent rational execution of the stereoselective transformations furnished the functionalized scaffold 38, whose coupling with a lipophilic segment under Wittig conditions, followed by deprotection and a THF core construction, completed the convergent synthesis of 2-epimer of 1. The final anhydrophytosphingosine 4.HCl was screened for its antiproliferative/cytotoxic activity employing multiple human cancer cell lines. In vitro evaluation revealed that 2-epi-jaspine B exhibited significant antitumour growth inhibitory activity against all used cells.