Title compounds I (R = H, 4-Me, 5-Me; Z = Cl2, O, S) and II (R1 = H, 3-Me, 4-Me; R2 = H, Me, halo, CO2H) were prepared E.g., stirring Cl3GeCH2CH2COCl with Na2S in MeCN at room temperature for 12 h gave 22% I (R = H, Z = Cl2), treatment of which with H2O in acetone gave 52% I (R = H, Z = O).

Key words: ANTICARCINOGEN, INFRARED SPECTROPHOTOMETRY, ELEMENTAL ANALYSIS, MASS SPECTROGRAPHY, PROTON MAGNETIC RESONANCE SPECTROMETRY, FIVE MEMBER RING HETEROCYCLIC COMPOUNDS, CYCLOPENTANONE P, SULFUR HETEROCYCLICS COMPOUNDS, ORGANO GERMANIUM