Heparanase is regarded as a promising target for anticancer drugs and Ronepastat is one of the most promising heparanase inhibitors insert in clinical study for Multiple Myeloma Therapy. To improve its pharmacokinetic/pharmacodynamic profile, as well to have an antidote able to neutralize its activity in case of over dosages or intolerance, a new class of its derivatives was obtained inserting non-carbohydrate moieties of different length between the polysaccharide chain and biotin or its derivatives. In vitro these novel derivatives maintain the anti-heparanase activity without induced toxicity. The newly synthesized compounds retained the ability to attenuate the growth of CAG myeloma tumors in mice with potency similar, or in one case even higher than that of the reference compound Roneparstat as well as inhibited metastatic dissemination (lung colonization) of murine B16-F10 melanoma cells in vivo. Display omitted •Heparanase is regarded as a promising target for anticancer drugs and Ronepastat is one of one of its most promising inhibitors.•A new class of biotinylated N-acetyl-gs-heparin have been synthetized through a linker of different functional groups.•Compounds were characterized by NMR and evaluation of molecular weight.•“in vitro” and “in vivo” tests showed that the chemical modifications introduced do not hinder their biological activity.