Cytisine is a quinolizidine alkaloid isolated from various Leguminosae plants. Cytisine and its derivatives exhibit a broad range of biological properties, such as smoking cessation aid, antidepressant, neuroprotective, nootropic, anticancer, antiviral, antiparasitic, antidiabetic, insecticidal, and nematicidal activities. In this review, the progress of cytisine and its derivatives in regard to bioactivities, total synthesis, structural modifications focusing on their N-12 position and lactam ring is reported. Additionally, the structure-activity relationships of cytisine and its derivatives are also discussed.

中文翻译：

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胱氨酸衍生物的生物活性，全合成，结构修饰和结构-活性关系的研究进展。

半胱氨酸是从多种豆科植物中分离得到的喹诺唑烷生物碱。半胱氨酸及其衍生物具有广泛的生物学特性，例如戒烟辅助，抗抑郁，神经保护，促智，抗癌，抗病毒，抗寄生虫，抗糖尿病，杀虫和杀线虫活性。在这篇综述中，报道了胱氨酸及其衍生物在生物活性，全合成，侧重于它们的N-12位置和内酰胺环的结构修饰方面的进展。此外，还讨论了胱氨酸及其衍生物的构效关系。