The target diosgenin-betulinic acid conjugates are reported to investigate their ability to enhance and modify the pharmacological effects of their components. The detailed synthetic procedure that includes copper(I)-catalyzed Huisgen 1,3-dipolar cycloaddition (click reaction), and palladium-catalyzed debenzylation by hydrogenolysis is described together with the results of cytotoxicity screening tests. Palladium-catalyzed debenzylation reaction of benzyl ester intermediates was the key step in this synthetic procedure due to the simultaneous presence of a 1,4-disubstituted 1,2,3-triazole ring in the molecule that was a competing coordination site for the palladium catalyst. High pressure (130 kPa) palladium-catalyzed procedure represented a successful synthetic step yielding the required products. The conjugate 7 showed selective cytotoxicity in human T-lymphoblastic leukemia (CEM) cancer cells (IC50 = 6.5 ± 1.1 µM), in contrast to the conjugate 8 showing no cytotoxicity, and diosgenin (1), an adaptogen, for which a potential to be active on central nervous system was calculated in silico. In addition, 5 showed medium multifarious cytotoxicity in human T-lymphoblastic leukemia (CEM), human cervical cancer (HeLa), and human colon cancer (HCT 116). Betulinic acid (2) and the intermediates 3 and 4 showed no cytotoxicity in the tested cancer cell lines. The experimental data obtained are supplemented by and compared with the in silico calculated physico-chemical and absorption, distribution, metabolism, and excretion (ADME) parameters of these compounds.

Department of Chemistry of Natural Compounds University of Chemistry and Technology Prague Technická 5 16628 Prague 6 Czech Republic

Department of NMR Spectroscopy Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences Flemingovo náměstí 2 16610 Prague 6 Czech Republic

Faculty of Nuclear Sciences and Physical Engineering Czech Technical University Prague Břehová 7 11519 Prague 1 Czech Republic

Isotope Laboratory Institute of Experimental Botany of the Czech Academy of Sciences Vídeňská 1083 14220 Prague 4 Czech Republic

Laboratory of Growth Regulators Faculty of Science Palacký University and Institute of Experimental Botany of the Czech Academy of Sciences Šlechtitelů 27 78371 Olomouc Czech Republic

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Shikov A.N., Pozharitskaya O.N., Makarova M.N., Makarov V.G., Wagner H. Bergenia crassifolia (L.) Fritsch–Pharmacology and phytochemistry. Phytomedicine. 2014;21:1534–1542. doi: 10.1016/j.phymed.2014.06.009. PubMed DOI

Zhu Y., Zhu H., Qiu M., Zhu T., Ni J. Investigation on the mechanisms for biotransformation of saponins to diosgenin. World J. Microbiol. Biotechnol. 2014;30:143–152. doi: 10.1007/s11274-013-1429-7. PubMed DOI

Özdemir Z., Bildziukevich U., Wimmerová M., Macůrková A., Lovecká P., Wimmer Z. Plant adaptogens: Natural medicaments for 21st century? ChemistrySelect. 2018;3:2196–2214. doi: 10.1002/slct.201702682. DOI

Raju J., Mehta R. Cancer Chemopreventive and therapeutic effects of diosgenin, a food saponin. Nutr. Cancer. 2009;61:27–35. doi: 10.1080/01635580802357352. PubMed DOI

Raju J., Patlolla J.M.R., Swamy M.V., Rao C.V. Diosgenin, a steroid saponin of Trigonella foenum graecum (Fenugreek), inhibits azoxymethane-induced aberrant crypt foci formation in F344 rats and induces apoptosis in HT-29 human colon cancer cells. Biomarkers Prevention. 2004;13:1392–1398. PubMed

Chojnacki J.E., Liu K., Saathoff J.M., Zhang S. Bivalent ligands incorporating curcumin and diosgenin as multifunctional compounds against Alzheimer’s disease. Bioorg. Med. Chem. 2015;23:7324–7331. doi: 10.1016/j.bmc.2015.10.032. PubMed DOI PMC

Šarek J., Kvasnica M., Vlk M., Urban M., Džubák P., Hajdúch M. The Potential of Triterpenoids in the Treatment of Melanoma. In: Murph M., editor. Research on Melanoma-a Glimpse into Current Directions and Future Trends. InTech; Rijeka, Croatia: 2011. pp. 125–158.

Šarek J., Kvasnica M., Vlk M., Biedermann D. Semisynthetic Lupane Derivatives with Cytotoxic Activity. In: Salvador J.A.R., editor. Pentacyclic Triterpenes as Promising Agents in Cancer. Nova Science Publishers; New York, NY, USA: 2010. pp. 159–189.

Pisha E., Chai H., Lee I.-S., Chagwedera T.E., Farnsworth N.R., Cordell G.A., Beecher C.W.W., Fong H.H.S., Kinghorn A.D., Brown D.M., et al. Discovery of betulinic acid as a selective inhibitor of human melanoma that functions by induction of apoptosis. Nat. Med. 1995;1:1046–1051. doi: 10.1038/nm1095-1046. PubMed DOI

Özdemir Z., Bildziukevich U., Šaman D., Havlíček L., Rárová L., Navrátilová L., Wimmer Z. Amphiphilic derivatives of (3β,17β)-3-hydroxyandrost-5-ene-17-carboxylic acid. Steroids. 2017;128:58–67. doi: 10.1016/j.steroids.2017.10.011. PubMed DOI

Bildziukevich U., Vida N., Rárová L., Kolář M., Šaman D., Havlíček L., Drašar P., Wimmer Z. Polyamine derivatives of betulinic acid and β-sitosterol: A comparative investigation. Steroids. 2015;100:27–35. doi: 10.1016/j.steroids.2015.04.005. PubMed DOI

Wimmerová M., Siglerová V., Šaman D., Šlouf M., Kaletová E., Wimmer Z. Improved enzyme-mediated synthesis and supramolecular self-assembly of naturally occurring conjugates of β-sitosterol. Steroids. 2017;117:38–43. doi: 10.1016/j.steroids.2016.09.009. PubMed DOI

Bildziukevich U., Kaletová E., Šaman D., Sievänen E., Kolehmainen E.T., Šlouf M., Wimmer Z. Spectral and microscopic study of self-assembly of novel cationic spermine amides of betulinic acid. Steroids. 2017;117:90–96. doi: 10.1016/j.steroids.2016.07.007. PubMed DOI

Bildziukevich U., Rárová L., Šaman D., Wimmer Z. Picolyl amides of betulinic acid as antitumor agents causing tumor cell apoptosis. Eur. J. Med. Chem. 2018;145:41–50. doi: 10.1016/j.ejmech.2017.12.096. PubMed DOI

Bildziukevich U., Rárová L., Janovská L., Šaman D., Wimmer Z. Enhancing effect of cystamine in its amides with betulinic acid as antimicrobial and antitumor agent in vitro. Steroids. 2019;148:91–98. doi: 10.1016/j.steroids.2019.04.004. PubMed DOI

Bildziukevich U., Malík M., Özdemir Z., Rárová L., Janovská L., Šlouf M., Šaman D., Šarek J., Wimmer Z. Spermine amides of selected triterpenoid acids: Dynamic supramolecular systems formation influences cytotoxicity of the drugs. J. Mater. Chem. B. 2020;8:484–491. doi: 10.1039/C9TB01957J. PubMed DOI

Vlk M., Urban M., Elbert T., Šarek J. Synthesis of selectively deuterated and tritiated lupane derivatives with cytotoxic activity. J. Radioanal. Nucl. Chem. 2013;298:1149–1157. doi: 10.1007/s10967-013-2533-8. DOI

Bori I.D., Hung H.-Y., Qian K., Chen C.-H., Morris-Natschke S.L., Lee K.-H. Anti-AIDS agents 88. Anti-HIV conjugates of betulin and betulinic acid with AZT prepared via click chemistry. Tetrahedron Lett. 2012;53:1987–1989. doi: 10.1016/j.tetlet.2012.02.022. PubMed DOI PMC

Rega M., Jiménez C., Rodríguez J. 6E-Hydroximinosteroid homodimerization by cross-metathesis processes. Steroids. 2007;72:729–735. doi: 10.1016/j.steroids.2007.03.014. PubMed DOI

Berg R., Straub B.F. Advancement in the mechanistic understanding of the copper-catalyzed azide-alkyne cycloaddition. Beilstein J. Org. Chem. 2013;9:2715–2750. doi: 10.3762/bjoc.9.308. PubMed DOI PMC

Brassard C.J., Zhang X., Brewer C.R., Liu P., Clark R.J., Zhu L. Cu(II)-catalyzed oxidative formation of 5,5′-bistriazoles. J. Org. Chem. 2016;81:12091–12105. doi: 10.1021/acs.joc.6b01907. PubMed DOI

Coleman R.S., Shah J.A. Chemoselective cleavage of benzyl ethers, esters, and carbamates in the presence of other easily reducible groups. Synthesis. 1999;S1:1399–1400. doi: 10.1055/s-1999-3664. DOI

Schmidt U., Kroner M., Griesser H. Total synthesis of didemnins; IV.1 Synthesis of peptolide ring and construction of the side chain. Synthesis. 1991;4:294–300. doi: 10.1055/s-1991-26448. DOI

Dov Ben I. The use of hydrogen bromide in acetic acid for the removal of carbobenzoxy groups and benzyl esters of peptide derivative. J. Org. Chem. 1954;19:62–66.

Farooq T., Sydnes L.K., Törnroos K.W., Haug B.E. Debenzylation of functionalized 4- and 5-substituted 1,2,3-triazoles. Synthesis. 2012;44:2070–2078.

Mbaveng A.T., Chi G.F., Nguenang G.S., Abdelfatah S., Sop R.V.T., Ngadjui T., Kuete V., Efferth T. Cytotoxicity of a naturally occurring spirostanol saponin, progenin III, towards a broad range of cancer cell lines by induction of apoptosis, autophagy and necroptosis. Chem. Biol. Interact. 2020;326:109141. doi: 10.1016/j.cbi.2020.109141. PubMed DOI

Advanced Chemistry Development, Version 12.02. Advanced Chemistry Development; Toronto, ON, Canada: 2011. software ACD/iLabs.

Lipinski C.A., Lombardo F., Dominy B.W., Feeney P.J. Experimental and computational approaches to estimate solubility and permeability in drug discovery and developmental settings. Adv. Drug Deliv. Rev. 2001;46:3–26. doi: 10.1016/S0169-409X(00)00129-0. PubMed DOI

Ghose A.K., Viswanadhan V.N., Wendoloski J.J. A knowledge-based approach in designing combinatorial or medicinal chemistry libraries for drug discovery. 1. A qualitative and quantitative characterization of known drug databases. J. Combin. Chem. 1999;1:55–68. doi: 10.1021/cc9800071. PubMed DOI

Dutt R., Garg V., Khatri N., Madan A.K. Phytochemicals in anticancer drug development. Anti-Cancer Agents Med. Chem. 2019;19:172–183. doi: 10.2174/1871520618666181106115802. PubMed DOI

Novel Oleanolic Acid-Tryptamine and -Fluorotryptamine Amides: From Adaptogens to Agents Targeting In Vitro Cell Apoptosis

Triterpenoid-PEG Ribbons Targeting Selectivity in Pharmacological Effects