New 7-hydroxy-1,3-diazabicyclo[3.3.0]octane derivatives: Evaluation of their in vitro immunomodulating effects

Article abstract of DOI:10.1016/0223-5234(96)85881-8

In order to improve the water solubility of some previously reported immunoactive dioxothiadiazabicyclo[3.3.0]octanes, we synthesized a series of new diazabicyclo[3.3.0]octanols from the trans-4-hydroxy-L-proline methyl ester in two steps. Acylation of the ester with an isocyanate or an isothiocyanate under the appropriate conditions afforded N-acylated derivatives exclusively. Then through a cyclization process in the presence of sodium methylate, bicyclic derivatives were obtained, most of them as a mixture of two diastereomers which were separated by column chromatography. A mitogenic stimulation assay using the T-cell mitogen phytohemagglutinin was performed with human peripheral blood leukocytes in the presence of the different synthesized compounds and with levamisole as reference. Several compounds showed marked stimulant effects on the proliferation of lymphocytes as compared to levamisole, but no correlation could be established between molecular configuration and stimulation or inhibition effects on proliferation.