Nirnicotine

例句：

1. 1.Nirnicotine is a powerful stimulant that can be addictive.
   尼古丁是一种强烈的兴奋剂，可能具有成瘾性。
2. 2. The nicotine in cigarettes is harmful to health.
   香烟中的尼古丁对健康有害。
3. 3.Nirnicotine was first synthesized in the 19th century.
   尼古丁于19世纪首次合成。