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.

• Keywords
• betulin, betulinic acid, biocatalysis, biotransformation, enzyme, extraction, lupane, lupeol, prodrugs, synthesis,
• MeSH
• Biocatalysis * MeSH
• Hydrolysis MeSH
• Drug Discovery MeSH
• Oxidation-Reduction MeSH
• Triterpenes chemical synthesis   chemistry   MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• lupane MeSH Browser
• Triterpenes MeSH

Brassinosteroids are a class of plant hormones that regulate a broad range of physiological processes such as plant growth, development and immunity, including the suppression of biotic and abiotic stresses. In this paper, we report the synthesis of new brassinosteroid analogues with a nitrogen-containing side chain and their biological activity on Arabidopis thaliana. Based on molecular docking experiments, two groups of brassinosteroid analogues were prepared with short and long side chains in order to study the impact of side chain length on plants. The derivatives with a short side chain were prepared with amide, amine and ammonium functional groups. The derivatives with a long side chain were synthesized using amide and ammonium functional groups. A total of 25 new brassinosteroid analogues were prepared. All 25 compounds were tested in an Arabidopsis root sensitivity bioassay and cytotoxicity screening. The synthesized substances showed no significant inhibitory activity compared to natural 24-epibrassinolide. In contrast, in low concentration, several compounds (8a, 8b, 8e, 16e, 22a and 22e) showed interesting growth-promoting activity. The cytotoxicity assay showed no toxicity of the prepared compounds on cancer and normal cell lines.

• Keywords
• brassinosteroid, cytotoxicity, nitrogen-containing steroid, organic synthesis, plant bioassay,
• MeSH
• Arabidopsis drug effects   growth & development   MeSH
• Brassinosteroids chemical synthesis   chemistry   pharmacology   MeSH
• Nitrogen chemistry   MeSH
• Molecular Structure MeSH
• Chemistry Techniques, Synthetic * MeSH
• Plant Development drug effects   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Brassinosteroids MeSH
• Nitrogen MeSH

The subject of this review article refers to the recent achievements in the investigation of pharmacological activity and supramolecular characteristics of betulinic acid and its diverse derivatives, with special focus on their cytotoxic effect, antitumor activity, and antiviral effect, and mostly covers a period 2015-2018. Literature sources published earlier are referred to in required coherences or from historical points of view. Relationships between pharmacological activity and supramolecular characteristics are included if such investigation has been done in the original literature sources. A wide practical applicability of betulinic acid and its derivatives demonstrated in the literature sources is also included in this review article. Several literature sources also focused on in silico calculation of physicochemical and ADME parameters of the developed compounds, and on a comparison between the experimental and calculated data.

• Keywords
• ADME parameters, antitumor activity, antiviral activity, betulinic acid, cytotoxicity, physicochemical parameters, structural modification, supramolecular self-assembly,
• MeSH
• Chemical Phenomena * MeSH
• Phytochemicals chemistry   isolation & purification   pharmacology   MeSH
• Betulinic Acid MeSH
• Humans MeSH
• Pentacyclic Triterpenes MeSH
• Triterpenes chemistry   isolation & purification   pharmacology   MeSH
• Structure-Activity Relationship MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• Phytochemicals MeSH
• Betulinic Acid MeSH
• Pentacyclic Triterpenes MeSH
• Triterpenes MeSH