Department of Organic Chemistry, Faculty of Science, Palacký University in Olomouc, 17. listopadu 12, 771 46 Olomouc, Czech Republic.
Medicinal Chemistry, Faculty of Medicine and Dentistry, Institute of Molecular and Translational Medicine, Palacký University in Olomouc, Hněvotínská 5, 779 00 Olomouc, Czech Republic.
Molecules. 2021 Apr 14;26(8):2271. doi: 10.3390/molecules26082271.
Pentacyclic triterpenes are important representatives of natural products that exhibit a wide variety of biological activities. These activities suggest that these compounds may represent potential medicines for the treatment of cancer and viral, bacterial, or protozoal infections. Naturally occurring triterpenes usually have several drawbacks, such as limited activity and insufficient solubility and bioavailability; therefore, they need to be modified to obtain compounds suitable for drug development. Modifications can be achieved either by methods of standard organic synthesis or with the use of biocatalysts, such as enzymes or enzyme systems within living organisms. In most cases, these modifications result in the preparation of esters, amides, saponins, or sugar conjugates. Notably, while standard organic synthesis has been heavily used and developed, the use of the latter methodology has been rather limited, but it appears that biocatalysis has recently sparked considerably wider interest within the scientific community. Among triterpenes, derivatives of lupane play important roles. This review therefore summarizes the natural occurrence and sources of lupane triterpenoids, their biosynthesis, and semisynthetic methods that may be used for the production of betulinic acid from abundant and inexpensive betulin. Most importantly, this article compares chemical transformations of lupane triterpenoids with analogous reactions performed by biocatalysts and highlights a large space for the future development of biocatalysis in this field. The results of this study may serve as a summary of the current state of research and demonstrate the potential of the method in future applications.
五环三萜类化合物是天然产物的重要代表，具有广泛的生物活性。这些活性表明，这些化合物可能代表治疗癌症以及病毒、细菌或原生动物感染的潜在药物。天然存在的三萜类化合物通常具有几个缺点，例如活性有限以及溶解度和生物利用度不足；因此，需要对其进行修饰以获得适合药物开发的化合物。修饰可以通过标准有机合成方法或使用生物催化剂（例如生物体中的酶或酶系统）来实现。在大多数情况下，这些修饰会导致酯、酰胺、皂苷或糖缀合物的制备。值得注意的是，虽然标准有机合成已经得到了广泛的应用和发展，但后一种方法的使用相当有限，但似乎生物催化最近在科学界引起了更广泛的兴趣。在三萜类化合物中，羽扇豆烷衍生物起着重要的作用。因此，本综述总结了羽扇豆烷三萜类化合物的天然存在和来源、生物合成以及半合成方法，这些方法可用于从丰富且廉价的白桦脂醇生产白桦脂酸。最重要的是，本文比较了五环三萜类化合物的化学转化与生物催化剂进行的类似反应，并强调了该领域生物催化未来发展的巨大空间。该研究的结果可以作为当前研究状况的总结，并展示该方法在未来应用中的潜力。
