The invention discloses novel 42-0-(heteroalkoxyalkyl) rapamycin compounds of formula (1) and process for preparation thereof. These compounds are useful in the treatment of hyperproliferative vascular diseases such as restenosis and atherosclerosis Wherein, R denotes 3, 4 and 5 membered 3-hydroxy heteroalkoxyalkyl compounds selected from Tetrahydrofuran-3-ol, Oxetan-3-ol, Tetrahydropyran-3-ol, Tetrahydro-4- methyl furan-3-ol, Tetrahydro-2,5,5-trimethyl furan-3-ol, Tetrahydro-2,5-diethyl-2-methyl furan-3-ol, Tetrahydro-6-methoxy-2-methyl 2H-Pyran-3-ol and Tetrahydro-2,2-dimethyl-6-phenyl 2H-Pyran-3-ol.
