New triazole-substituted triterpene derivatives exhibiting anti-RSV activity: synthesis, biological evaluation, and molecular modeling

• Elenilson F. da Silva,
• Krist Helen Antunes Fernandes,
• Denise Diedrich,
• Jessica Gotardi,
• Marcia Silvana Freire Franco,
• Carlos Henrique Tomich de Paula da Silva,
• Ana Paula Duarte de Souza and
• Simone Cristina Baggio Gnoatto

Beilstein J. Org. Chem. 2022, 18, 1524–1531, doi:10.3762/bjoc.18.161

• the same region occupied by crystallographic ligands in their complex with IMPDH. The results obtained in this study suggest that compound 8 might be a new anti-RSV candidate. Keywords: antiviral; betulinic acid; bioisosterism; respiratory syncytial virus; triterpene; ursolic acid; Introduction

• ]. Ursanes, represented by ursolic acid and lupanes, represented by betulinic acid, both natural pentacyclic triterpenes, are commonly found in several plant species could provide interesting prototypes for developing new antivirals, more specifically anti-RSV compounds [21]. Betulinic (1) and ursolic (2

• , several studies have shown that semisynthetic triterpenes with modifications at the C-3 and C-28 positions might have the potential to be anti-human immunodeficiency virus type-1 (HIV-1) drugs [24][25][26][27]. Bevirimat, a betulinic acid derivative modified at the C-3 position, demonstrated secure

Cytochrome P450 monooxygenase-mediated tailoring of triterpenoids and steroids in plants

• Karan Malhotra and
• Jakob Franke

Beilstein J. Org. Chem. 2022, 18, 1289–1310, doi:10.3762/bjoc.18.135

• , which plays a central role in the diversification of triterpenoids in eudicots [79]. Members of the CYP716A subfamily were mostly identified as C28 oxidases that catalyse three-step oxidation of α-amyrin (7), β-amyrin (6) and lupeol (10) to ursolic acid, oleanolic acid, and betulinic acid, respectively

On the application of 3d metals for C–H activation toward bioactive compounds: The key step for the synthesis of silver bullets

• Renato L. Carvalho,
• Amanda S. de Miranda,
• Mateus P. Nunes,
• Roberto S. Gomes,
• Guilherme A. M. Jardim and
• Eufrânio N. da Silva Júnior

Beilstein J. Org. Chem. 2021, 17, 1849–1938, doi:10.3762/bjoc.17.126

• these results, the late-stage diversification using the [Mn(t-BuPc)Cl] catalyst was applied to more complex natural compounds such as the isosteviol derivative 45 and the betulinic acid derivative 47, which underwent conversion in good and high yields and with high chemoselectivity. The functionalized

• isosteviol derivate furnished a useful and versatile oxathiazinane (46). The betulinic acid-derived sulfamate ester preferentially underwent amination at the γ primary C–H bond of the equatorial C23 methyl group with high site- and diastereoselectivity to furnish the oxathiazinane derivative in 76% yield

Chemical constituents of Chaenomeles sinensis twigs and their biological activity

• Joon Min Cha,
• Dong Hyun Kim,
• Lalita Subedi,
• Zahra Khan,
• Sang Un Choi,
• Sun Yeou Kim and
• Chung Sub Kim

Beilstein J. Org. Chem. 2020, 16, 3078–3085, doi:10.3762/bjoc.16.257

• ], ethyl β-ᴅ-glucopyranoside (5) [30], n-butyl-α-ᴅ-fructofuranoside (6) [31], genistein 5-glucoside (7) [32], apigenin (8) [33], betulin (9) [3], betulinic acid (10) [34], betulinal (11) [35], and tormentic acid (12) [3] by comparison of their spectroscopic data with the reported data. In the course of

• against four human tumor cell lines A549, SK-OV-3, SK-MEL-2, and BT549 using a sulforhodamine B (SRB) assay. Of the three lupane-type triterpenoids (9–11), betulin (9) and betulinic acid (10) showed potent cytotoxicity with IC50 values of 4.2–8.7 μM against all four tumor cell lines whereas betulinal (11

• ) exhibited mild growth inhibitory effects against A549 and BT549 cell lines with IC50 values of 27.1 and 22.7 μM, respectively (Table 2). Betulinic acid (10) is a well-known anticancer agent inhibiting eukaryotic topoisomerase I [36] and its derivatives have been reported to display cytotoxic activity [13

An overview of recent advances in duplex DNA recognition by small molecules

• Sayantan Bhaduri,
• Nihar Ranjan and
• Dev P. Arya

Beilstein J. Org. Chem. 2018, 14, 1051–1086, doi:10.3762/bjoc.14.93

• betulinic acid analogs were synthesized by using azide–alkyne click reaction and their anticancer activities against different cancer cell lines and normal human PBMC cell line were evaluated by MTT assay. Conjugate 42 was found to be extremely potent against HT-29 cell line with an IC50 value of 14.9 μM

Synthesis of five- and six-membered cyclic organic peroxides: Key transformations into peroxide ring-retaining products

• Alexander O. Terent'ev,
• Dmitry A. Borisov,
• Vera A. Vil’ and
• Valery M. Dembitsky

Beilstein J. Org. Chem. 2014, 10, 34–114, doi:10.3762/bjoc.10.6

• synthesized by the oxidation of triterpenes 149a–d with Na2Cr2O7/N-hydroxysuccinimide (Scheme 36). The resulting compounds exhibit antitumor activity comparable with that of betulinic acid [175][176][177]. 1.6. Structural modifications, in which the 1,2-dioxolane ring remains intact The possibility of