tricyclic compounds

例句：

1. 1. The molecule of thiscompound is made up of three rings.
   这种化合物的分子由三个环组成。
2. 2. This compoundhas been found in nature and is usedas a source of energy.
   这种化合物已在自然界中发现，并用作能源来源。
3. 3. The discoveryof this compound has sparked interest inthe study of organic chemistry.
   这种化合物的发现激发了有机化学研究的兴趣。