The application is directed to compounds of Formula I’-A, and especially to compounds of Formula I-Aand pharmaceutically acceptable salts and solvates thereof, wherein R1a-R5a, Y, Za are defined as set forth in the specification. The invention is also directed to use of compounds of Formula I’-A, and especially compounds of Formula I-A, to treat disorders responsive to the modulation of one or more opioid receptors, or as synthetic intermediates. Certain compounds of the present invention are especially useful for treating pain.本發明係有關式I’-A之化合物，且特別是有關式I-A之化合物及其藥學上可接受之鹽類與溶劑化物，其中R1a至R5a、Y、Za係如說明書中所定義。本發明也有關式I’-A之化合物，特別是式I-A之化合物於治療對一或多種類鴉片受體的調控有反應之病症上的用途，或用作為合成中間物。本發明之一些化合物特別可用於治療疼痛。
