abstract |
The present invention has a structure of 7, 9, 16, and 20 shown in FIG. 1 and has a proton nuclear magnetic resonance spectrum of 6, 8, 12, and 14 degrees and a carbon nuclear magnetic resonance spectrum of 7, 9, 13, and 15 degrees, respectively. The present invention relates to the synthesis of anti-asthmatic substances that antagonize hydroxycoten-based leukotriene D4 and its efficacy. |