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

Synthesis and anticancer profile of novel sphingoid base-like compounds with a quaternary stereocentre

The synthesis of novel sphingoid base-like compounds with a quaternary stereocentre was achieved in a sequence featuring [3,3]-sigmatropic rearrangements and olefin cross-metathesis transformation as the key reaction steps, which were accompanied by the rational selection of suitable functional group transformations. The stereochemistry of the desired tetra-substituted carbon bearing nitrogen functionality was determined via NOESY experiments of the advanced oxazolidine-2-thiones. Cell viability experiments revealed significant antiproliferative/cytotoxic activity of the target compounds 7, ent-7 and 29 against the Jurkat cell line, with the IC₅₀ values of 6.6 μM, 5.6 μM and 6.1 μM, respectively.

Stereoselective synthesis and antiproliferative activity of the isomeric sphinganine analogues

A flexible synthetic approach to biologically active sphingoid base-like compounds with a 3-amino-1,2-diol framework was achieved through a [3,3]-sigmatropic rearrangement and late stage olefin cross-metathesis as the key transformations. The stereochemistry of the newly created stereogenic centre was assigned via a single crystal X-ray analysis of the (4S,5R)-5-(hydroxymethyl)-4-vinyloxazolidine-2-thione. In order to rationalise the observed stereoselectivity of the aza-Claisen rearrangement, DFT calculations were carried out. The targeted isomeric sphingoid bases were screened in vitro for anticancer activity on a panel of seven human malignant cell lines. Cell viability experiments revealed that C₁₇-homologues are more active than their C₁₂ congeners.

Synthesis and biological activity of sphingosines with integrated azobenzene switches

The synthesis of photochromic active sphingosine analogues and their antiproliferative activity against seven human cancer cell lines is reported.

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.