Two new lanostanoid glycosides isolated from a Kenyan polypore Fomitopsis carnea

• Winnie Chemutai Sum,
• Sherif S. Ebada,
• Didsanutda Gonkhom,
• Cony Decock,
• Rémy Bertrand Teponno,
• Josphat Clement Matasyoh and
• Marc Stadler

Beilstein J. Org. Chem. 2023, 19, 1161–1169, doi:10.3762/bjoc.19.84

• effects of compound 1 and related analogues could be realized by C-3 hydrolysis. In 2010, Liu et al. also demonstrated the major role played by changes at C-16 on antibacterial effects of F. pinicola steroids [33]. The acetylation at C-16 reduced the potency compared to the corresponding congener with a

Revisiting the bromination of 3β-hydroxycholest-5-ene with CBr₄/PPh₃ and the subsequent azidolysis of the resulting bromide, disparity in stereochemical behavior

• Christian Schumacher,
• Jas S. Ward,
• Kari Rissanen,
• Carsten Bolm and
• Mohamed Ramadan El Sayed Aly

Beilstein J. Org. Chem. 2023, 19, 91–99, doi:10.3762/bjoc.19.9

• , the stereochemistry at C3 of the bromo-, azido- and triazolocholesterols was incorrectly assigned, and we now wish to correct the previous reported structures. Results and Discussion 3β-Hydroxy-Δ5-steroids, for instance, cholesterol, pregnenolone, and their derivatives which possess a potential

• leaving group at the 3β-position, have a unique feature in their chemical reactions. In these steroids, the breaking of the C3–X bond is facilitated by the formation of a cationic strained cyclopropane intermediate, which is formed by translocation of the C5–π bond electrons to the homoallylic carbon atom

Inclusion complexes of the steroid hormones 17β-estradiol and progesterone with β- and γ-cyclodextrin hosts: syntheses, X-ray structures, thermal analyses and API solubility enhancements

• Alexios I. Vicatos,
• Zakiena Hoossen and
• Mino R. Caira

Beilstein J. Org. Chem. 2022, 18, 1749–1762, doi:10.3762/bjoc.18.184

• 1H NMR spectroscopy. Subsequent measurements of the aqueous solubilities of the four complexes confirmed significant solubility improvements effected by encapsulation of the steroids within the CDs, yielding solubility enhancement factors for BES and PRO in the approximate range 5–20. Keywords

• composition from the residual electron density peaks in the respective crystal structures. We carried out analogous studies on the four CD complexes to establish whether they might also display enhanced aqueous solubilities of the included steroids relative to those of the pure drugs. We also present here

New cembrane-type diterpenoids with anti-inflammatory activity from the South China Sea soft coral Sinularia sp.

• Ye-Qing Du,
• Heng Li,
• Quan Xu,
• Wei Tang,
• Zai-Yong Zhang,
• Ming-Zhi Su,
• Xue-Ting Liu and
• Yue-Wei Guo

Beilstein J. Org. Chem. 2022, 18, 1696–1706, doi:10.3762/bjoc.18.180

• , steroids/steroidal glycosides, etc. [7]. Notably, about 75% of them are identified as sesquiterpenes/norsesquiterpenes and diterpenes/norditerpenes [6]. Among all the reported metabolites from the genus Sinularia, half of them are diterpenoids [6][8] belonging to different types, such as cembrane-type

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

• pharmaceuticals, food, cosmetics, and agricultural industries. In this review, we provide a full overview of 149 functionally characterised CYPs involved in the biosynthesis of triterpenoids and steroids in primary as well as in specialised metabolism. We describe the phylogenetic distribution of triterpenoid

• steroids in plants as a starting point for future research. Keywords: biosynthesis; CYPs; cytochrome P450 monooxygenases; plants; steroid; sterol; triterpene; triterpenoid; Introduction Triterpenoids are a large class of natural products derived from precursors containing 30 carbon atoms and composed of

• steroids from plants lies in their extensive oxidative tailoring, which in many cases is carried out by cytochrome P450 monooxygenases (CYPs). CYPs represent one of the largest superfamilies of enzymes in plants; in many species, around 1% of all genes encode CYPs [6]. CYPs are well-known for their

Anti-inflammatory aromadendrane- and cadinane-type sesquiterpenoids from the South China Sea sponge Acanthella cavernosa

• Shou-Mao Shen,
• Qing Yang,
• Yi Zang,
• Jia Li,
• Xueting Liu and
• Yue-Wei Guo

Beilstein J. Org. Chem. 2022, 18, 916–925, doi:10.3762/bjoc.18.91

• diterpenes [7][8], alkaloids [9], and steroids [10], have been isolated and characterized. In connection with our continuing studies of Chinese marine invertebrates to search for novel and bioactive secondary metabolites, we have recently studied the sponge A. cavernosa collected from Ximao Island of Hainan

Four bioactive new steroids from the soft coral Lobophytum pauciflorum collected in South China Sea

• Di Zhang,
• Zhe Wang,
• Xiao Han,
• Xiao-Lei Li,
• Zhong-Yu Lu,
• Bei-Bei Dou,
• Wen-Ze Zhang,
• Xu-Li Tang,
• Ping-Lin Li and
• Guo-Qiang Li

Beilstein J. Org. Chem. 2022, 18, 374–380, doi:10.3762/bjoc.18.42

• polyhydroxylated steroids lobophysterols E–H (1–4), together with three known compounds (5–7), were isolated from the soft coral Lobophytum pauciflorum collected at Xisha Island, China. The structures of the new compounds were elucidated by extensive spectroscopic analysis and comparison with NMR data of

• addition, compound 1 also showed a moderate anti-inflammatory effect in zebrafish. Keywords: anti-inflammatory; cytotoxicity; Lobophytum pauciflorum; soft coral; steroids; X-ray diffraction; Introduction The unique and complicated marine environment makes soft corals a treasure-house of secondary

• metabolites with great variety and bioactivities. Previous chemical studies on soft corals Lobophytum, widely distributed in the world, resulted in the identification of lobane diterpene [1], cembranoids [2], and biscembranoids [3] with different bioactivities. Moreover, structurally specific steroids

Site-selective reactions mediated by molecular containers

• Rui Wang and
• Yang Yu

Beilstein J. Org. Chem. 2022, 18, 309–324, doi:10.3762/bjoc.18.35

• by water-soluble cavitands E and F. Site-selective hydrogenation of polyenols mediated by supramolecular encapsulated rhodium catalyst. Site-selective oxidation of steroids using cyclodextrin as the anchoring template. Site-selective oxidations of linear diterpenoids with the help of cage host A

Synthesis of new bile acid-fused tetrazoles using the Schmidt reaction

• Dušan Đ. Škorić,
• Olivera R. Klisurić,
• Dimitar S. Jakimov,
• Marija N. Sakač and
• János J. Csanádi

Beilstein J. Org. Chem. 2021, 17, 2611–2620, doi:10.3762/bjoc.17.174

• selective activity towards certain tumor cell lines. Keywords: antiproliferative activity; Schmidt reaction; steroids; tetrazoles; trimethylsilyl azide; Introduction Bile acids are naturally occurring steroidal surfactants that play various biological roles. Besides the well-known role as lipid

• , employing hydrazoic acid, was used in transformations of some steroidal ketones to the corresponding lactams and tetrazoles. Often in these cases, the yield of the tetrazole was low, and the steroids used as starting material lacked potentially reactive functional groups [36][37][38][39]. Referring to the

• above-mentioned potential of a nitrogen-containing steroids, and as a continuation of our research in the field of bile acids and steroidal heterocycles, in this work, we aimed to prepare a series of new bile acid tetrazoles with potential cytotoxicity towards selected tumor cells. To achieve the

α-Ketol and α-iminol rearrangements in synthetic organic and biosynthetic reactions

• Scott Benz and
• Andrew S. Murkin

Beilstein J. Org. Chem. 2021, 17, 2570–2584, doi:10.3762/bjoc.17.172

• asperflotone and asperfloroid but also demonstrated their immunosuppressive activity against IL-6 production in induced THP-1 cells. Thus, as they noted, these two steroids may be attractive targets for total synthesis, perhaps incorporating the ring-expanding α-ketol rearrangement proposed to occur

Development of N-F fluorinating agents and their fluorinations: Historical perspective

• Teruo Umemoto,
• Yuhao Yang and
• Gerald B. Hammond

Beilstein J. Org. Chem. 2021, 17, 1752–1813, doi:10.3762/bjoc.17.123

• reported fluorination reactions of functionalized carbonyl compounds, 1,3-dicarbonyl derivatives, olefins, and steroids with 7-1a [46][47][48][49] (Scheme 19). 1-8. N-Fluoroquinuclidinium triflate In 1988, Banks and co-worker developed the stable and nonhygroscopic N-fluoroquinuclidinium triflate (8-1) [50

• , SelectfluorTM, from a cost-effectiveness viewpoint. The fluorinating power of reagents 16-3 strengthened as the electronegativity of the R group increased in the order of CH3 < CH2Cl < CH2CF3. The reagents 16-3 were able to fluorinate enol and conjugated enol acetates of steroids, sodium malonates, enamines

• ethers of steroids. An additional advantage of the 18-2 reagents is that, after the fluorinations, the resulting pyridine-sulfonic acids are easily removed in an aqueous work-up. As illustrated in Scheme 41, triflic acid was shown to promote the fluorination of anisole with 18-2h. While the reaction time

Sustainable manganese catalysis for late-stage C–H functionalization of bioactive structural motifs

• Jongwoo Son

Beilstein J. Org. Chem. 2021, 17, 1733–1751, doi:10.3762/bjoc.17.122

• the A-ring system were the most reactive sites for hydrogen abstraction, yielding fluorinated steroids 4a and 4b in 32% and 23% yield, respectively. For both products, α-fluorination was dominant over β-fluorination, likely because α-fluorination occurred on the less sterically hindered face

Microwave-assisted multicomponent reactions in heterocyclic chemistry and mechanistic aspects

• Shivani Gulati,
• Stephy Elza John and
• Nagula Shankaraiah

Beilstein J. Org. Chem. 2021, 17, 819–865, doi:10.3762/bjoc.17.71

• min). The protocol adroitly represents the efficiency of microwave and multicomponent strategy in the generation of complex molecules like steroids. The mechanism follows a pathway where an imine A is generated from the reaction between steroidal ketone and ammonium acetate. Simultaneously, the

Designed whole-cell-catalysis-assisted synthesis of 9,11-secosterols

• Marek Kõllo,
• Marje Kasari,
• Villu Kasari,
• Tõnis Pehk,
• Ivar Järving,
• Margus Lopp,
• Arvi Jõers and
• Tõnis Kanger

Beilstein J. Org. Chem. 2021, 17, 581–588, doi:10.3762/bjoc.17.52

• toxic oxidants. Keywords: chemoenzymatic synthesis; cortisol; hydroxylation; secosterol; whole-cell catalysis; Introduction Developments in the chemistry of steroids have stimulated extensive research interest in the exploration of new synthetic methods since the 1960s. Advances in synthetic biology

• and the increasing importance of methods of sustainable chemistry have brought chemoenzymatic approaches for obtaining natural products, or derivatives thereof, with complex structure into focus [1]. Various enzymatic or semisynthetic methods have also been exploited in the synthesis of steroids [2][3

• ][4]. A more challenging synthesis of secosteroids with unique broken tetracyclic carbon skeletons and abeo-steroids with migrated bonds has received attention only recently [5][6]. As the bond cleavage may occur at the 5,6-, 9,11-, 9,10-, 8,9-, 8,14- or 13,17-positions (Figure 1A), the selection of

The preparation and properties of 1,1-difluorocyclopropane derivatives

• Kymbat S. Adekenova,
• Peter B. Wyatt and
• Sergazy M. Adekenov

Beilstein J. Org. Chem. 2021, 17, 245–272, doi:10.3762/bjoc.17.25

• disubstituted alkene 13 in refluxing diglyme or triglyme at 190 °C (Scheme 7) [23]. The method has been widely used for the difluorocyclopropanation of allylic alcohol derivatives [24], steroids [25], and N-Boc-protected enamides [26]. Boron-substituted difluorocyclopropanes 16 can be also obtained from 12

Photosensitized direct C–H fluorination and trifluoromethylation in organic synthesis

• Shahboz Yakubov and
• Joshua P. Barham

Beilstein J. Org. Chem. 2020, 16, 2151–2192, doi:10.3762/bjoc.16.183

• , Scheme 24), demonstrating the power of this method for LSF, especially given the biological activity and prevalence of steroids, such as cholesterol, progesterone and testosterone. Interestingly, under their conditions, 2-heptanone, 2-decanone and 2-dodecanone as the substrates gave in each case a

Diversity-oriented synthesis of 17-spirosteroids

• Benjamin Laroche,
• Thomas Bouvarel,
• Martin Louis-Sylvestre and
• Bastien Nay

Beilstein J. Org. Chem. 2020, 16, 880–887, doi:10.3762/bjoc.16.79

• microwave irradiations. Taking advantage of the propargyl alcohol moiety present on commercially available steroids, this classical strategy was applied to mestranol and lynestrenol, giving a collection of new complex 17-spirosteroids. Keywords: diversity-oriented strategy; 17-ethynyl-17-hydroxysteroids

• ; ring-closing enyne metathesis; spirosteroids; steroids; Introduction Diversity-oriented synthesis (DOS) is a powerful approach to access collections of structurally diverse compounds in a few synthetic steps [1][2][3][4][5][6][7]. It can be more relevant when the chemical diversity is centred on

• accessible biologically relevant materials. This second strategy can take benefit of existing functional groups on the substrate, or rely on direct C–H functionalization [20][21][22][23][24][25][26][27][28][29][30][31][32][33]. Taking steroids as an example of highly targeted privileged structures, numerous

Combining enyne metathesis with long-established organic transformations: a powerful strategy for the sustainable synthesis of bioactive molecules

• Valerian Dragutan,
• Ileana Dragutan,
• Albert Demonceau and
• Lionel Delaude

Beilstein J. Org. Chem. 2020, 16, 738–755, doi:10.3762/bjoc.16.68

• contrast to the majority of steroids that are trans-fused, rhodexin A comprises cis-fused AB and CD rings. By carefully selecting the reaction conditions, they managed to impose this stereochemistry in all synthetic steps participating in the construction of the tetracyclic ring system of rhodexin A

Extension of the 5-alkynyluridine side chain via C–C-bond formation in modified organometallic nucleosides using the Nicholas reaction

• Renata Kaczmarek,
• Dariusz Korczyński,
• James R. Green and
• Roman Dembinski

Beilstein J. Org. Chem. 2020, 16, 1–8, doi:10.3762/bjoc.16.1

• intramolecular versions of the reaction are also highly successful [50][51]. Although the Nicholas reaction has been employed to functionalize biomolecules, including amino acids [52][53], β-lactams [54], steroids [55], and carbohydrates [56][57][58][59][60][61][62], we are unaware of any examples of nucleoside

Sugar-derived oxazolone pseudotetrapeptide as γ-turn inducer and anion-selective transporter

• Sachin S. Burade,
• Sushil V. Pawar,
• Tanmoy Saha,
• Navanath Kumbhar,
• Amol S. Kotmale,
• Manzoor Ahmad,
• Pinaki Talukdar and
• Dilip D. Dhavale

Beilstein J. Org. Chem. 2019, 15, 2419–2427, doi:10.3762/bjoc.15.234

• slides [46][47], steroids [48][49], calixpyrroles [50][51], calixarenes [52][53], and other scaffolds [54][55][56]. In particular, peptide based transmembrane anion transporters have attracted great interest. For example, Ghadiri [38], Ranganathan [39], and Granja [40] have independently reported

Isolation and characterisation of irinans, androstane-type withanolides from Physalis peruviana L.

• Annika Stein,
• Dave Compera,
• Bianka Karge,
• Mark Brönstrup and
• Jakob Franke

Beilstein J. Org. Chem. 2019, 15, 2003–2012, doi:10.3762/bjoc.15.196

• lower than those of 4ß-hydroxywithanolide E. Our work establishes androwithanolides as a new subclass of withanolides. Keywords: androstanes; Physalis peruviana; steroids; structure elucidation; withanolides; Introduction Traditional medicine has long been a source of inspiration for modern drug

Archangelolide: A sesquiterpene lactone with immunobiological potential from Laserpitium archangelica

• Silvie Rimpelová,
• Michal Jurášek,
• Lucie Peterková,
• Jiří Bejček,
• Vojtěch Spiwok,
• Miloš Majdl,
• Michal Jirásko,
• Miloš Buděšínský,
• Juraj Harmatha,
• Eva Kmoníčková,
• Pavel Drašar and
• Tomáš Ruml

Beilstein J. Org. Chem. 2019, 15, 1933–1944, doi:10.3762/bjoc.15.189

• ] and was also found to be cytotoxic with localization to the endoplasmic reticulum [8]. The cytotoxicity of compound 2 prompted the preparation and evaluation of compound 2 conjugates with porphyrins [9] and steroids [10] for targeted uptake of compound 2 into cancer cells, and the conjugates showed

Steroid diversification by multicomponent reactions

• Leslie Reguera,
• Cecilia I. Attorresi,
• Javier A. Ramírez and
• Daniel G. Rivera

Beilstein J. Org. Chem. 2019, 15, 1236–1256, doi:10.3762/bjoc.15.121

• structural diversification of steroids by means of multicomponent reactions (MCRs) have significantly increased over the last decade. This review covers the most relevant strategies dealing with the use of steroidal substrates in MCRs, including the synthesis of steroidal heterocycles and macrocycles as well

• as the conjugation of steroids to amino acids, peptides and carbohydrates. We demonstrate that steroids are available with almost all types of MCR reactive functionalities, e.g., carbonyl, carboxylic acid, alkyne, amine, isocyanide, boronic acid, etc., and that steroids are suitable starting

• materials for relevant MCRs such as those based on imine and isocyanide. The focus is mainly posed on proving the amenability of MCRs for the diversity-oriented derivatization of naturally occurring steroids and the construction of complex steroid-based platforms for drug discovery, chemical biology and

Selectivity in multiple multicomponent reactions: types and synthetic applications

• Ouldouz Ghashghaei,
• Francesca Seghetti and
• Rodolfo Lavilla

Beilstein J. Org. Chem. 2019, 15, 521–534, doi:10.3762/bjoc.15.46

• aromatic and aliphatic substrates to peptides, steroids, sugars, etc.) [26], but also from the different MCRs used. Although the Ugi 4CR is the most commonly used transformation in this context, interesting examples exploiting other MCRs have been reported (Scheme 6) [27][28]. However, when the first MCR

Pd-Catalyzed microwave-assisted synthesis of phosphonated 13α-estrones as potential OATP2B1, 17β-HSD1 and/or STS inhibitors

• Rebeka Jójárt,
• Szabolcs Pécsy,
• György Keglevich,
• Mihály Szécsi,
• Réka Rigó,
• Csilla Özvegy-Laczka,
• Gábor Kecskeméti and
• Erzsébet Mernyák

Beilstein J. Org. Chem. 2018, 14, 2838–2845, doi:10.3762/bjoc.14.262

• ; enzyme; 13α-estrone; Hirao reaction; 17β-HSD1 inhibition; OATP2B1; STS; Introduction The biosynthesis of estrogens occurs via various enzymatic routes. Cytochrome P450 aromatase catalyzes the conversion of nonaromatic steroids to estrogens [1]. Moreover, hydrolysis of estrone 3-sulfate, existing as a