A new class of rapamycin 40-O-cyclic hydrocarbon esters is disclosed. The 40-O position of the rapamycin ester has the form 40-O—R, where R is C(O)—(CH2)n-X, n is 0, 1 or 2, and X is a cyclic hydrocarbon having 3-8 carbons, optionally containing one or more unsaturated bonds, and one or more linear (CH2)n) and/or cyclic (X) carbon atoms may have an OH or halide group. Also disclosed are therapeutic compositions and methods that employ the novel analogs.