| 摘要 |
An analgic agent which comprises a compound of general formula (I), wherein each of R1 and R2 is a hydrogen atom or an optionally substituted hydrocarbon group; R3 is a lower alkyl group; rings A and B may optionally be substituted; ring D is further substituted with an optionally substituted hydroxyl group and may optionally be substituted with an oxo group, wherein a double bond is formed between the positions 8 and 9 or between the positions 9 and 10, or a pharmaceutically acceptable salt thereof, and a production thereof. |
