In vitro evaluation of the novel cycloalkyl-N-(4-chlorophenyl)-hydroxamic acids (2a-g) demonstrates that the compounds 2b, d, e and g exhibited rather marked inhibitory activity (IC50 = 7-10 uM) against malignant tumor cell lines: colon carcinoma (SW620), laryngeal carcinoma (Hep2), pancreatic carcinoma (MiaPaCa2). Compound 2e showed the most pronounced anti-CMV activity (EC50 = 1.5 and 0.8 ug mL-1) only at ≥ 5-fold lower than the cytotoxic concentration. Compounds 2d and 2f showed modest, albeit selective activity against cytomegalovirus (2d: EC50 = 7.3-8.9 ug mL-1, selectivity index 7-10, and 2f: EC50 = 7-13 ug mL-1 and selectivity index 10).