Chemoenzymatic synthesis of the cardenolide rhodexin A and its aglycone sarmentogenin

• Fuzhen Song,
• Mengmeng Zheng,
• Dongkai Wang,
• Xudong Qu and
• Qianghui Zhou

Beilstein J. Org. Chem. 2025, 21, 2637–2644, doi:10.3762/bjoc.21.204

• reagent [20], the key intermediate 8 bearing a butenolide motif was obtained in 76% yield. Next, with the aid of the strong Lewis acid Bi(OTf)3, the regioselective elimination of 8 was achieved to produce the Δ14 olefin intermediate 9 in 86% yield. Afterwards, we evaluated the reactivity of 9 towards

• glycosylation. To our delight, as shown in Scheme 3B, with TMSOTf as the promoter, the glycosylation between 11 and 14 proceeded smoothly in a stereospecific manner, delivering the key intermediate 15 in 98% yield. Subsequently, treating 15 under Mn(acac)2-catalyzed Mukaiyama hydration conditions yielded the

Visible-light-driven NHC and organophotoredox dual catalysis for the synthesis of carbonyl compounds

• Vasudevan Dhayalan

Beilstein J. Org. Chem. 2025, 21, 2584–2603, doi:10.3762/bjoc.21.200

• of single-electron NHC catalysis by incorporating oxidatively generated aryloxymethyl radicals A as a key intermediate. A variety of γ-aryloxy ketones 12 were successfully prepared in the presence of NHC (15 mol %), photocatalyst (2 mol %), using 467 nm LED and a combination of alkene 11, amide 9

Recent advances in total synthesis of illisimonin A

• Juan Huang and
• Ming Yang

Beilstein J. Org. Chem. 2025, 21, 2571–2583, doi:10.3762/bjoc.21.199

• cation were consistent with earlier reports [2][26], though the configurations of the intermediates were clearly delineated. The authors proposed that dicarbonyl compound 50 serves as the key intermediate diverging to all Illicium sesquiterpenes, with a retro-Dieckmann condensation and aldol reaction

• reductive Heck reaction of 59 enabled the transannular connection between C4 and C5, generating key intermediate 60, which possesses the same carbon skeleton as the proposed biosynthetic key intermediate 50 and contains the suitable functional groups for further elaboration. Mukaiyama hydration of 60

Total syntheses of highly oxidative Ryania diterpenoids facilitated by innovations in synthetic strategies

• Zhi-Qi Cao,
• Jin-Bao Qiao and
• Yu-Ming Zhao

Beilstein J. Org. Chem. 2025, 21, 2553–2570, doi:10.3762/bjoc.21.198

• compound 19. This intermediate is converted to lactone 20 via base-promoted Grob fragmentation followed by acid-mediated MOM deprotection. Epoxidation of the C10–C11 double bond in 20, lactone hydrolysis-promoted epoxide ring opening, and inversion of the C10 hydroxy configuration, yield the key

• intermediate 21, thereby completing the construction of the D ring. Adjustments of functional groups and oxidation states at multiple sites then afford anhydroryanodol (10). Finally, epoxidation of the C1–C2 double bond followed by Li/NH3-promoted reductive cyclization constructs the E ring of the molecular

Synthetic study toward vibralactone

• Liang Shi,
• Jiayi Song,
• Yiqing Li,
• Jia-Chen Li,
• Shuqi Li,
• Li Ren,
• Zhi-Yun Liu and
• Hong-Dong Hao

Beilstein J. Org. Chem. 2025, 21, 2376–2382, doi:10.3762/bjoc.21.182

• this key intermediate in hand, β-hydroxy acid 29 was synthesized through deprotection, IBX oxidation, and Pinnick–Lindgren–Kraus oxidation and the β-lactone 13 was subsequently obtained through activation of the carboxylic acid. Although we successfully constructed the molecular scaffold of

Comparative analysis of complanadine A total syntheses

• Reem Al-Ahmad and
• Mingji Dai

Beilstein J. Org. Chem. 2025, 21, 2334–2344, doi:10.3762/bjoc.21.178

• . to forge the C2–C3’ bipyridyl linkage and produce 56 in good yield [30]. From 56, a one-pot Cbz removal and pyridine N-oxide reduction completed their total synthesis of complanadine A. In addition, 56 also served as a key intermediate for their synthesis of complanadine B, which was achieved via a

Research towards selective inhibition of the CLK3 kinase

• Vinay Kumar Singh,
• Frédéric Justaud,
• Dabbugoddu Brahmaiah,
• Nangunoori Sampath Kumar,
• Blandine Baratte,
• Thomas Robert,
• Stéphane Bach,
• Chada Raji Reddy,
• Nicolas Levoin and
• René L. Grée

Beilstein J. Org. Chem. 2025, 21, 2250–2259, doi:10.3762/bjoc.21.172

• anilinoquinazoline 3a. Deprotection of the methoxy group by BBr3 gave phenol 4a which was propargylated to intermediate 5a. A final click-type reaction [27][28][29][30][31] with azide 6 gave the first target intermediate 7a. The second key intermediate 7b was prepared in a very similar manner, but starting from 3

C2 to C6 biobased carbonyl platforms for fine chemistry

• Jingjing Jiang,
• Muhammad Noman Haider Tariq,
• Florence Popowycz,
• Yanlong Gu and
• Yves Queneau

Beilstein J. Org. Chem. 2025, 21, 2103–2172, doi:10.3762/bjoc.21.165

• further converted to C4 bulk chemicals such as 2,3-butanediol and butene (Scheme 27). 1,4-Dihydroxybutan-2-one 1,4-Dihydroxybutan-2-one is a key intermediate for the synthesis of different polyols such as 2-aminobutane-1,4-diol. Ma and co-workers synthesized 1,4-dihydroxybutan-2-one by a benzaldehyde

• phosphorus oxide catalyst (VPO), furoic acid was also found to be a key intermediate (Scheme 44, route b) [149]. A photocatalytic access to succinic anhydride from furoic acid using catalytic porphyrin H2TPP in the presence of O2 and light was also reported [150]. Yang and Lv reported the oxidation of

• , amides, lactones, acrylic acid, etc. (Scheme 72) and is therefore a key intermediate in the synthesis of pharmaceuticals, agrochemicals, and other specialty chemicals. Levulinate esters, used as a solvent or as biofuels, are obtained by esterification under acid catalysis, e.g., with a sulfuric acid

Formal synthesis of a selective estrogen receptor modulator with tetrahydrofluorenone structure using [3 + 2 + 1] cycloaddition of yne-vinylcyclopropanes and CO

• Jing Zhang,
• Guanyu Zhang,
• Hongxi Bai and
• Zhi-Xiang Yu

Beilstein J. Org. Chem. 2025, 21, 1639–1644, doi:10.3762/bjoc.21.127

• is the retrosynthetic analysis for the key intermediate 1, which can reach the final compound VI via chlorination and demethylation [19]. Target molecule 1 can be accessed by decarboxylation reaction from compound 13, prepared by an intramolecular Heck reaction between the β-ketoester and the vinyl

Heterologous biosynthesis of cotylenol and concise synthesis of fusicoccane diterpenoids

• Ye Yuan,
• Zhenhua Guan,
• Xue-Jie Zhang,
• Nanyu Yao,
• Wenling Yuan,
• Yonghui Zhang,
• Ying Ye and
• Zheng Xiang

Beilstein J. Org. Chem. 2025, 21, 1489–1495, doi:10.3762/bjoc.21.111

• pathway of brassicicenes in Aspergillus oryzae and harnessing the promiscuity of a cytochrome P450 from the biosynthesis of fusicoccin A (Figure 1b). A key intermediate, brassicicenes I (5), was further used to achieve the collective synthesis of alterbrassicicene E (6), brassicicenes A (7) and R (8

• cotylenin A and cotylenol (Figure 3a). Oxidation of brassicicene I with Dess–Martin reagent afforded intermediate 9 in 92% yield. The tertiary hydroxy group of compound 9 was further protected with a TMS group to provide compound 10 in 90% yield, a key intermediate in the synthesis of cotylenol and

Oxetanes: formation, reactivity and total syntheses of natural products

• Peter Gabko,
• Martin Kalník and
• Maroš Bella

Beilstein J. Org. Chem. 2025, 21, 1324–1373, doi:10.3762/bjoc.21.101

• intramolecular E2 elimination. Finally, the importance and power of the intramolecular Williamson etherification has also been demonstrated by the kilogram-scale synthesis of oxetane intermediate 41, which is a key intermediate in the preparation of the previously mentioned IDO1 inhibitor 2 (Scheme 9) [16

Recent advances in oxidative radical difunctionalization of N-arylacrylamides enabled by carbon radical reagents

• Jiangfei Chen,
• Yi-Lin Qu,
• Ming Yuan,
• Xiang-Mei Wu,
• Heng-Pei Jiang,
• Ying Fu and
• Shengrong Guo

Beilstein J. Org. Chem. 2025, 21, 1207–1271, doi:10.3762/bjoc.21.98

A versatile route towards 6-arylpipecolic acids

• Erich Gebel,
• Cornelia Göcke,
• Carolin Gruner and
• Norbert Sewald

Beilstein J. Org. Chem. 2025, 21, 1104–1115, doi:10.3762/bjoc.21.88

• aryl modifications in C6 position by utilising the chiral pool of a non-proteinogenic amino acid in combination with transition metal-catalysed cross-coupling reactions. Moreover, we present an in-depth NMR analysis of the key intermediate steps, which illustrates the conformational constraints in

• a key intermediate product. This late-stage approach was previously described by us while utilising Suzuki–Miyaura or Sonogashira–Hagihara cross-coupling reactions to generate pipecolic acid derivatives with alkynyl substituents in the C6 position [35]. Here, we present a robust synthetic route to

Studies on the syntheses of β-carboline alkaloids brevicarine and brevicolline

• Benedek Batizi,
• Patrik Pollák,
• András Dancsó,
• Péter Keglevich,
• Gyula Simig,
• Balázs Volk and
• Mátyás Milen

Beilstein J. Org. Chem. 2025, 21, 955–963, doi:10.3762/bjoc.21.79

• , Semmelweis University, Üllői út 26, H-1085 Budapest, Hungary 10.3762/bjoc.21.79 Abstract A new total synthesis of the β-carboline alkaloid brevicarine is disclosed. The synthesis was carried out starting from an aromatic triflate key intermediate, allowing the introduction of various substituents into

• their accessibility for pharmacological measurements. Results and Discussion In the present study, we aimed to develop a novel, scalable synthesis of brevicarine (2) and an alternative synthetic approach for the preparation of brevicolline (1), both based on the common key intermediate 3 [9]. The

Recent advances in controllable/divergent synthesis

• Jilei Cao,
• Leiyang Bai and
• Xuefeng Jiang

Beilstein J. Org. Chem. 2025, 21, 890–914, doi:10.3762/bjoc.21.73

• represents a highly challenging direct C(sp3)–H asymmetric amination. Mechanistic insights: When using a bulky, electron-rich chiral bisphosphine ligand L6, the glycine ester substrate coordinates with the copper catalyst to form a key intermediate complex Int-26. The sterically hindered and electron-rich

• mechanism for the formation of the key intermediate 69 is outlined in Scheme 19: first, substrate 67, under the action of a copper catalyst and diisopropylethylamine, undergoes a decarboxylation process to generate the allylidenecopper intermediate Int-63 and its resonance form Int-64. Subsequently, these

Light-enabled intramolecular [2 + 2] cycloaddition via photoactivation of simple alkenylboronic esters

• Lewis McGhie,
• Hannah M. Kortman,
• Jenna Rumpf,
• Peter H. Seeberger and
• John J. Molloy

Beilstein J. Org. Chem. 2025, 21, 854–863, doi:10.3762/bjoc.21.69

• ). Pioneering studies have leveraged this platform with great effect, typically invoking π→π* transitions of conjugated alkenes to lower the bond order and generate a triplet diradical, primed for further reactivity. This key intermediate is pivotal in a plenum of synthetic transformations including geometric

Asymmetric synthesis of fluorinated derivatives of aromatic and γ-branched amino acids via a chiral Ni(II) complex

• Maurizio Iannuzzi,
• Thomas Hohmann,
• Michael Dyrks,
• Kilian Haoues,
• Katarzyna Salamon-Krokosz and
• Beate Koksch

Beilstein J. Org. Chem. 2025, 21, 659–669, doi:10.3762/bjoc.21.52

• iodides can be efficiently synthesized in gram-scale from the respective fluorinated alcohols using alkyl nonaflates as a key intermediate [13]. Based on these results, 3,3,3-trifluoro-2-methylpropan-1-ol (8) was selected as the starting material. We started our efforts by screening the reaction

Streamlined modular synthesis of saframycin substructure via copper-catalyzed three-component assembly and gold-promoted 6-endo cyclization

• Asahi Kanno,
• Ryo Tanifuji,
• Satoshi Yoshida,
• Sota Sato,
• Saori Maki-Yonekura,
• Kiyofumi Takaba,
• Jungmin Kang,
• Kensuke Tono,
• Koji Yonekura and
• Hiroki Oguri

Beilstein J. Org. Chem. 2025, 21, 226–233, doi:10.3762/bjoc.21.14

• structure of 16 was confirmed by serial X-ray crystallography using an X-ray free-electron laser (XFEL) [deposition number CCDC 2352718) [54][55]. We then performed a Strecker-type reaction on the aldehyde 16 to construct an α-aminonitrile 17. To our delight, the key intermediate, 2,3-diaminobenzofuran 11

• measurements (Figures S20 to S25, Supporting Information File 1). A notable feature of this cascade process is the temporary protection of the C≡N triple bond, nitrile in the key intermediate 11, by the 2,3-diaminobenzofuran group. This facilitates the site-selective activation of the alkyne triple bond by the

• –Spengler-type reactions. (c) This work: streamlined modular assembly featuring copper(I)-catalyzed regiocontrolled three-component coupling (8 → 10), one-pot formation of the 2,3-diaminobenzofuran ring in the key intermediate 11, and subsequent gold(I)-mediated regiocontrolled 6-endo hydroamination

Synthesis, characterization, and photophysical properties of novel 9‑phenyl-9-phosphafluorene oxide derivatives

• Shuxian Qiu,
• Duan Dong,
• Jiahui Li,
• Huiting Wen,
• Jinpeng Li,
• Yu Yang,
• Shengxian Zhai and
• Xingyuan Gao

Beilstein J. Org. Chem. 2024, 20, 3299–3305, doi:10.3762/bjoc.20.274

• was achieved in 5 steps starting from commercially available 2-bromo-4-fluoro-1-nitrobenzene (1, Scheme 1 and Scheme 2). For the preparation of the key intermediate 5 (Scheme 1), self-coupling of 1 in the presence of copper followed by reduction of the nitro group generated diamine compound 3 (89

• room temperature. (a) PL spectra of the PhFlOP-based emitters 7 measured in toluene at room temperature. (b) PL spectra of 7-H measured in different solvents at room temperature. Preparation of key intermediate 5. Synthesis of PhFlOP-based molecules 7. Crystal data and structural parameters for 7-H

Multicomponent reactions driving the discovery and optimization of agents targeting central nervous system pathologies

• Lucía Campos-Prieto,
• Aitor García-Rey,
• Eddy Sotelo and
• Ana Mallo-Abreu

Beilstein J. Org. Chem. 2024, 20, 3151–3173, doi:10.3762/bjoc.20.261

• was withdrawn from phase III clinical trials due to insufficient efficacy compared to current antipsychotic drugs (APDs). However, POM demonstrated to be effective to treat certain populations [69]. The large-scale synthesis of a key intermediate of POM was described by Waser et al. [70] in 2011. In

• /cyclization approach. General synthesis of 2,3-dichlorophenylpiperazine-derived compounds by the Ugi reaction and Ugi/deprotection/cyclization approach. Bucherer–Bergs multicomponent reaction to obtain a key intermediate in the synthesis of pomaglumetad methionil (POM). Ugi reaction to synthesize racetam

Advances in radical peroxidation with hydroperoxides

• Oleg V. Bityukov,
• Pavel Yu. Serdyuchenko,
• Andrey S. Kirillov,
• Gennady I. Nikishin,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2024, 20, 2959–3006, doi:10.3762/bjoc.20.249

• )] [40]. Introduction of the tert-butylperoxy fragment into the allylic position of substituted cyclohexenes 6 was carried out using Pd(OAc)2 in ambient conditions (Scheme 5) [41]. The corresponding allylic peroxy ethers 7 were synthesized in 62–75% yields, the key intermediate was proposed to be L2Pd(OO

Copper-catalyzed yne-allylic substitutions: concept and recent developments

• Shuang Yang and
• Xinqiang Fang

Beilstein J. Org. Chem. 2024, 20, 2739–2775, doi:10.3762/bjoc.20.232

• acetylide-bonded allylic cation as the key intermediate is proposed (Scheme 6a). It is worth noting that the nucleophilic attack favors a less sterically hindered site. Therefore, disubstituted alkene moiety prefers γ-attack while trisubstituted alkene moiety is inclined to α-attack (Scheme 6b). Lin and He

• vinyl allenylidene is the key intermediate during the process (Scheme 14). Recently, Fang et al. [67] used electron-rich arenes as the nucleophiles to achieve remote enantioselective control of yne-allylic substitutions. It is worth noting that when indoles or indolizines were used, the reactions

Photoredox-catalyzed intramolecular nucleophilic amidation of alkenes with β-lactams

• Valentina Giraldi,
• Giandomenico Magagnano,
• Daria Giacomini,
• Pier Giorgio Cozzi and
• Andrea Gualandi

Beilstein J. Org. Chem. 2024, 20, 2461–2468, doi:10.3762/bjoc.20.210

• from the commercially available β-lactam 9, a key intermediate for the industrial preparation of carbapenems. Starting from the reaction conditions reported by Nicewicz and Morse [28], we optimized the conditions with compound 8c as the model substrate for the photoredox cyclization (Table 1). The

Homogeneous continuous flow nitration of O-methylisouronium sulfate and its optimization by kinetic modeling

• Jiapeng Guo,
• Weike Su and
• An Su

Beilstein J. Org. Chem. 2024, 20, 2408–2420, doi:10.3762/bjoc.20.205

• 10.3762/bjoc.20.205 Abstract Nitration of O-methylisouronium sulfate under mixed acid conditions gives O-methyl-N-nitroisourea, a key intermediate of neonicotinoid insecticides with high application value. The reaction is a fast and highly exothermic process with a high mass transfer resistance, making

Asymmetric organocatalytic synthesis of chiral homoallylic amines

• Nikolay S. Kondratyev and
• Andrei V. Malkov

Beilstein J. Org. Chem. 2024, 20, 2349–2377, doi:10.3762/bjoc.20.201

• concerted SN2-key intermediate 60 must be at least 18.9 kcal/mol more favoured than a separated imine–chloride ion pair 61 attacked by the free allylsilane (Figure 3). Altogether, the developed methodology can be formally viewed as a useful tool for the enantioselective synthesis of chiral α-carboxyl-2,3