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A large series of disubstituted fulleropyrrolidines was synthesized and analyzed by cyclic voltammetry. The three main groups of target compounds differ by a flexible N-chain, while their further diversity was achieved by the introduction of various rigid, aryl substituents at the pyrrolidine carbon. Some dialkyl analogues were also designed for comparison, A standard [3+2]- cycloaddition of in situ generated azomethine ylides to C60 afforded a variety of disubstituted fulleropyrrolidines. Furthermore, a set of dumbbell-shaped di(fulleropyrrolidine) derivatives containing rigid fumaryl or isophthaloyl diamide platform was prepared with the aim of investigating a long-range effect of the second fulleropyrrolidine moiety on their electrochemical properties. All compounds were fully characterized by comparative analysis of spectral data, while examination of electrochemical properties was performed on representative samples, distinguished by main structural subunits. All compounds expressed quite similar electron-accepting ability, lower than C60, but higher in comparison to structurally similar N-methylfulleropyrrolidine.

Synthesis of a steroidal dendrimer core possessing various functional termini, such as ester, carboxy and hydroxy, is presented. The approach described enables further simple manipulations for the introduction of more complex functionalities.

A simple approach to a stable steroidal estrone derived A,B-spiro system is reported. Treatment of estrone derived A-ring diepoxyalcohol with the Ac(2)O-TMSOTf system at the ambient temperature led to acetylation, while at the reflux temperature the acid-catalysed rearrangement took place affording the spiro-compound. Results of extensive in vitro and in vivo anticancer tests on the diepoxide, as well as preliminary data on the antiproliferative activity of the spiro-product against three cancer cell lines, are also presented.

A simple approach to aromatization of steroidal quinols and epoxyquinols using a catalytic amount of TMSOTf is reported. Beside acetylation of the angular OH, the acid-catalyzed (TfOH) dienone-phenol rearrangement occurred affording "para" products, or in the case of blocked position 4, the acetoxy group 1,2-migration leads to the formation of "meta" products. Using epoxyquinol derivative as a substrate, the acetoxy group elimination was observed, followed by acid-catalyzed epoxy-ring opening and subsequent double bond migration, giving as a final product Delta(9,11)A-ring aromatized compounds. Synthesis of conduritol-like compounds and structure confirmation by X-ray crystallography of the precursor of steroidal conduritol is also described. In addition, the results of extensive antiproliferative screening against a panel of 60 cancer cell lines are presented.