Search results
Search for "tricyclic" in Full Text gives 272 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Chemoenzymatic synthesis of the cardenolide rhodexin A and its aglycone sarmentogenin
Beilstein J. Org. Chem. 2025, 21, 2637–2644, doi:10.3762/bjoc.21.204
- -electron demand Diels–Alder (IEDDA) reaction was utilized to successfully construct the BCD tricyclic structure with the correct configuration of the four contiguous stereocenters in just one step. However, the requirement of a series of protecting group manipulations undermined the step-economy and
Recent advances in total synthesis of illisimonin A
Beilstein J. Org. Chem. 2025, 21, 2571–2583, doi:10.3762/bjoc.21.199
- encumbered tricyclic lactone 84 via an intramolecular [6 + 2] cycloaddition (Scheme 8). Attempts to achieve an asymmetric version of the cycloaddition were unsuccessful. Treatment of the lactone with MeMgBr, followed by mesylation and elimination of the resulting hemiacetal, afforded enol ether 85. Reaction
Total syntheses of highly oxidative Ryania diterpenoids facilitated by innovations in synthetic strategies
Beilstein J. Org. Chem. 2025, 21, 2553–2570, doi:10.3762/bjoc.21.198
- constructed the ABC tricyclic core skeleton of the target molecule. This achievement transformed a simple monocyclic precursor into a complex fused-ring skeleton, vividly demonstrating the application value of the multi-reaction synergistic strategy in natural product synthesis. The specific synthetic route
- bond, and a subsequent transannular aldol reaction efficiently assembles the B and C rings, yielding the ABC tricyclic core 16. Further manipulations included the introduction of a methyl group at C9, adjustments of the oxidation state, and the installation of a mesylate group at C10, leading to
- symmetric motif within the complex pentacyclic target, the authors designed a simplified C2-symmetric tricyclic intermediate, (±)-33, which was efficiently synthesized in 13 steps from commercial starting materials 31 and 32 by capitalizing on its molecular symmetry. A notable feature of this sequence was
Transformation of the cyclohexane ring to the cyclopentane fragment of biologically active compounds
Beilstein J. Org. Chem. 2025, 21, 2416–2446, doi:10.3762/bjoc.21.185
- a sterically compact [6-5-5] tricyclic skeleton, as well as a highly strained trans-fused bicyclo[3.3.0]octane ring system and seven contiguous stereocenters. A structurally interesting diol 52 was diastereoselectively obtained using a linear sequence of 14 steps starting from the readily available
- in two steps [70]. The intermediate tricyclic ketone 137 was converted to the corresponding α-diazoketone through treatment with 2,4,6-triisopropylbenzenesulfonyl azide (trisylN3), KOH, tetrabutylammonium bromide (TBAB), and 18-crown-6. Concurrent cleavage of the benzoyl group under basic conditions
Recent advances in Norrish–Yang cyclization and dicarbonyl photoredox reactions for natural product synthesis
Beilstein J. Org. Chem. 2025, 21, 2315–2333, doi:10.3762/bjoc.21.177
- Terpenoids 1.1 (+)-Cyclobutastellettolide B (+)-Cyclobutastellettolide B (13), featuring an unusual 6/6/4-fused tricyclic core with six stereocenters – including three contiguous quaternary stereocenters – was first isolated by Stonik et al. in 2019 from a Stelletta sp. sponge collected in Vietnamese waters
Insoluble methylene-bridged glycoluril dimers as sequestrants for dyes
Beilstein J. Org. Chem. 2025, 21, 2302–2314, doi:10.3762/bjoc.21.176
- found that the water-soluble naphthalene-walled glycoluril dimer G2M2 (Figure 1) – with its roughly co-planar aromatic walls – is selective for planar aromatic cations as guests [38]. In order the complement the tricyclic ring system present in the panel of dyes (Figure 2), we envisioned the use of even
Enantioselective radical chemistry: a bright future ahead
Beilstein J. Org. Chem. 2025, 21, 2283–2296, doi:10.3762/bjoc.21.174
- tolerated a range of substituents on the olefin, giving the products with high enantioselectivity. Reactions of chiral β-methyl-substituted aldehydes 11 and 12 with indene (13) yielded tricyclic products with good diastereoselectivity and particularly high optical purity (99% ee). Organo-SOMO catalysis was
Pathway economy in cyclization of 1,n-enynes
Beilstein J. Org. Chem. 2025, 21, 2260–2282, doi:10.3762/bjoc.21.173
- delivered tricyclic indole derivative 59 featuring an exocyclic Z-alkene (Scheme 13, path a). When the terminal substituent of the alkyne was an aryl group, C3-selective cyclization was triggered under BiCl3 catalysis to generate tricyclic iminium 60. Subsequent aryl-assisted Mannich cyclization efficiently
- ring. This work presents an efficient synthetic approach for two structurally complex classes of pentacyclic spiroindolines and tricyclic indoles of pharmacological significance. In 2023, the Liu group reported a controllable cyclization strategy for indole substrates featuring a 1,6-enyne motif, which
- conditions, the authors attenuated the silver catalyst’s activity through ligand addition. This allowed for a umpolung addition of the substrate 87, affording six-membered spirocyclic intermediate 88. When the NFSI was used as ligand without nucleophiles, the tricyclic azepinoindole 89 was obtained via a
Thiadiazino-indole, thiadiazino-carbazole and benzothiadiazino-carbazole dioxides: synthesis, physicochemical and early ADME characterization of representatives of new tri-, tetra- and pentacyclic ring systems and their intermediates
Beilstein J. Org. Chem. 2025, 21, 2220–2233, doi:10.3762/bjoc.21.169
- 1,1-dioxide structural element. Results and Discussion We synthesized target compounds 3 exhibiting new tricyclic (3a–c, 3f–h, Scheme 1, Table 1) and tetracyclic (3d,e,i,j) ring systems starting from 8-chloro-2,4-dimethyl-2H-1,2,3-benzothiadiazine 1,1-dioxide (4a) and 8-chloro-2-methyl-4-phenyl-2H
Electrochemical cyclization of alkynes to construct five-membered nitrogen-heterocyclic rings
Beilstein J. Org. Chem. 2025, 21, 2173–2201, doi:10.3762/bjoc.21.166
- vinyl radical intermediate D. The radical in D reacted with the pyridyl N atom regioselectively to form a tricyclic radical E, which proceeded one-electron oxidation/hydrolysis afforded 49. Additionally, the imidazopyridines could be constructed through electrochemical intramolecular [3 + 2] annulation
C2 to C6 biobased carbonyl platforms for fine chemistry
Beilstein J. Org. Chem. 2025, 21, 2103–2172, doi:10.3762/bjoc.21.165
- alkane fuels (bicyclopentane, tricyclic alkane and spirocyclic alkane) through hydrodeoxygenation [205][206][207][208][209][210]. A cycloalkane with a density of 0.89 g/cm3 and a freezing point below −60 °C was prepared from CPN and lignin-derived vanillin. An overall yield of 95.2% of mono- and di
The application of desymmetric enantioselective reduction of cyclic 1,3-dicarbonyl compounds in the total synthesis of terpenoid and alkaloid natural products
Beilstein J. Org. Chem. 2025, 21, 2085–2102, doi:10.3762/bjoc.21.164
- of 57 to phenolic intermediate followed by the construction of the B ring generated tricyclic core 59. Subsequently, dihydroxylation of the doubled bond in the central six-membered ring using OsO4/NMO gave diol, which was then subjected to acetylation of the two hydroxy groups and hydrogenation of C5
- transformations of 121 generated bromodiene 122. Next, the metal–halogen exchange/intermolecular addition of 122 with aldehyde (+)-123 and in situ PtCl2-promoted hydrolysis and hydration gave tricyclic product 124. The BnMe3NOH-mediated intramolecular Michael/aldol cascade reaction of 124 constructed the C/D
Bioinspired total syntheses of natural products: a personal adventure
Beilstein J. Org. Chem. 2025, 21, 2048–2061, doi:10.3762/bjoc.21.160
- cyclization to forge the spirocycle in one step represents a comparably more powerful method to rapidly generate complexity, since the de novo synthesis approach by Cuny and co-workers [42] has inevitably met with a lot of problems on stereoselectivity although they started the synthesis from a tricyclic
Asymmetric total synthesis of tricyclic prostaglandin D2 metabolite methyl ester via oxidative radical cyclization
Beilstein J. Org. Chem. 2025, 21, 1964–1972, doi:10.3762/bjoc.21.152
- pathophysiological mediator in many human diseases and biological pathways. Tricyclic prostaglandin D2 metabolite methyl ester (tricyclic-PGDM methyl ester), the major urinary metabolite of PGD2, can be used as a clinical indicator for PGD2 overproduction. However, the limited amount of tricyclic-PGDM methyl ester
- available has prevented its practical use, and synthesis methods for tricyclic-PGDM methyl ester are required. Based on the utilization of oxidative radical cyclization for the stereoselective construction of the cyclopentanol subunit with three consecutive stereocenters, we describe an asymmetric total
- synthesis of tricyclic-PGDM methyl ester in 9 steps and 8% overall yield. Keywords: asymmetric total synthesis; oxidative radical cyclization; tricyclic prostaglandin D2 metabolite methyl ester; Introduction Prostaglandins (PGs), a family of hormone-like lipid compounds, are ubiquitous natural products
Approaches to stereoselective 1,1'-glycosylation
Beilstein J. Org. Chem. 2025, 21, 1700–1718, doi:10.3762/bjoc.21.133
- the orthogonally protected diol acceptor 36, proved to deliver optimal stereoselectivity and the highest yields in the reaction promoted by bistrifluoromethylated tricyclic borinic acid 40, affording β,α-1,1'-linked disaccharides 37 [63] and 39 [62], respectively, in 86% yield (Scheme 4). The nature
- 3,4,6-tri-O-benzylated 1,2-anhydroglucose 129 using an organoboron catalyst (Scheme 11). In situ-generated tricyclic borinate complexes (formed between 1,2-glycosyl diols and diarylborinic acids) effectively promoted the glycosylation with glycosyl anhydro sugars, yielding the 1,1'-α,α-trehalose
Formal synthesis of a selective estrogen receptor modulator with tetrahydrofluorenone structure using [3 + 2 + 1] cycloaddition of yne-vinylcyclopropanes and CO
Beilstein J. Org. Chem. 2025, 21, 1639–1644, doi:10.3762/bjoc.21.127
- frontier for treating breast cancer, osteoporosis, cardiovascular disease, neuropathies, and other diseases. Merck scientists found that molecules with tetrahydrofluorenone (6/5/6 tricyclic motif) can act as SERMs. For example, molecules I and II (Scheme 1A) displayed low nanomolar affinity for ERβ and
3-Aryl-2H-azirines as annulation reagents in the Ni(II)-catalyzed synthesis of 1H-benzo[4,5]thieno[3,2-b]pyrroles
Beilstein J. Org. Chem. 2025, 21, 1595–1602, doi:10.3762/bjoc.21.123
- ester group. In our case, the demethoxycarbonylative annulation enables the formation of aromatic tricyclic benzo[4,5]thieno[3,2-b]pyrrole system which is encountered in compounds with antitumor activity [21][22] as well as in compounds exhibiting fluorescent properties [22][23]. Since general methods
Heterologous biosynthesis of cotylenol and concise synthesis of fusicoccane diterpenoids
Beilstein J. Org. Chem. 2025, 21, 1489–1495, doi:10.3762/bjoc.21.111
- biosynthesis; P450 oxidation; synthesis; Introduction Fusicoccanes are a family of 5-8-5 tricyclic diterpenoid natural products that are produced by bacteria, fungi, algae, and plants (Figure 1a) [1][2][3][4][5][6][7]. Fusicoccanes possess a broad range of biological activities, including anticancer, anti
- Nozaki–Hiyama–Kishi reaction and a one-pot Prins cyclization/transannular hydride transfer to construct the 5-8-5 tricyclic scaffold. Enzymatic oxidations were used to install the hydroxy group at the C-3 position. Ten fusicoccanes were synthesized in 8–13 steps each. Despite these efforts, a strategy
- brassicicene biosynthesis-related gene cluster (BGC) in Alternaria brassicicola and Pseudocercospora fijiensis [34][35]. The 5-8-5 tricyclic scaffold is transformed into various fusicoccane natural products catalyzed by P450s, dioxygenases, dehydrogenases, and reductases. Therefore, we propose to harness the
Oxetanes: formation, reactivity and total syntheses of natural products
Beilstein J. Org. Chem. 2025, 21, 1324–1373, doi:10.3762/bjoc.21.101
- performing the reaction under visible light irradiation, or coupling the reaction to other light-induced processes to produce new classes of products. In 2018, Aitken and co-workers reported a synthesis of previously unknown tricyclic 4:4:4 oxetanes 73 through a photochemical triple cascade reaction starting
- utilised a HATU-promoted amide formation involving 3-(methylamino)oxetane (192) in the first step and the resulting bi- and tricyclic products 193 and 194 containing 6- and 7-membered rings were obtained in high yields (Scheme 48a). The second methodology generated similar polycyclic systems but used a
Recent total synthesis of natural products leveraging a strategy of enamide cyclization
Beilstein J. Org. Chem. 2025, 21, 999–1009, doi:10.3762/bjoc.21.81
- the terminal alkene and the conformational strain of forming a bridge[3.2.1]bicycle might be responsible for a selective 6-exo-trig cyclization. From tricyclic compound 4, anti-Markovnikov oxidation catalyzed by palladium led to the formation of aldehyde 5. When treated with p-TsOH, the intramolecular
- . Cyclization/isomerization – collective total synthesis of fawcettimine-type alkaloids The bicyclic decahydroquinoline enamide motif can serve as a versatile precursor to access different types of tricyclic N-heterocycles. As demonstrated in the above work from She’s group, the aza-Prins cyclization renders
- acetylcholinesterase (AChE) inhibitory activities [18]. In the presence of a catalytic amount of PPh3AuCl and AgSbF6, the enamide–alkyne cycloisomerization of bromo-substituted alkyne 8 proceeded via a 5-endo-dig cyclization to afford tricyclic compound 10 through the formation of iminium intermediate 9. The azepane
Silver(I) triflate-catalyzed post-Ugi synthesis of pyrazolodiazepines
Beilstein J. Org. Chem. 2025, 21, 915–925, doi:10.3762/bjoc.21.74
- formation of the tricyclic triazolo[1,5-a][1,4]benzodiazepine scaffold 10 (Scheme 1b) [39]. Triple bond-containing Ugi adducts showed a great promise for the assembly of various seven-membered nitrogen-containing heterocyclic cores through transition-metal-catalyzed alkyne hydroarylations [40][41][42][43
Recent advances in controllable/divergent synthesis
Beilstein J. Org. Chem. 2025, 21, 890–914, doi:10.3762/bjoc.21.73
- ligand-controlled regioselective migratory insertion process, reaction of Int-21 and Int-22 leads to the formation of π-allylpalladium intermediates Int-23 or Int-24, depending on the ligand employed. Finally, cyclization of Int-23 or Int-24 yields the tricyclic product 13 or the tetracyclic product 14
Total synthesis of (±)-simonsol C using dearomatization as key reaction under acidic conditions
Beilstein J. Org. Chem. 2025, 21, 601–606, doi:10.3762/bjoc.21.47
- , including insecticidal, antibacterial, anti-inflammatory, analgesic, and neurotrophic activities [3]. In 2013, Wang’s group isolated (±)-simonsol C from star anise, which features a unique 6/5/6 tricyclic benzofuran structure [4]. They found that it exhibits biological activity that promotes neuronal
- oxy-Michael addition from dienone 15. The 6/6/6 tricyclic structure in 15 can be constructed through dearomatization of compound 16, which in turn can be readily synthesized through consecutive alkylation steps starting from magnolol (11). Additionally, using magnolol as the starting material brings
- elimination was utilized to liberate the allyl group and to simultaneously construct the 6/5/6 tricyclic skeleton via an oxy-Michael addition affording (±)-simonsol C in 70% yield (Scheme 4). The spectral data were in agreement with the reported ones [4][15][16] and the cis relation between the protons at C5
Synthesis of N-acetyl diazocine derivatives via cross-coupling reaction
Beilstein J. Org. Chem. 2025, 21, 490–499, doi:10.3762/bjoc.21.36
- azobenzenes, spiropyranes and diarylethenes in organic solvents [3][13][15]. There are two strategies of applying diazocines in photopharmacology. The first one exploits the structural similarity of the tricyclic diazocine framework to the tricyclic structure of, e.g., tetrahydrodibenzazocines [16][17] and
Visible-light-promoted radical cyclisation of unactivated alkenes in benzimidazoles: synthesis of difluoromethyl- and aryldifluoromethyl-substituted polycyclic imidazoles
Beilstein J. Org. Chem. 2025, 21, 234–241, doi:10.3762/bjoc.21.15
- as a vital pharmacophore in medicinal chemistry due to its special biological activity [11][12][13]. In particular, the tricyclic benzimidazole skeleton is ubiquitous in many bioactive compounds and therapeutic agents (Figure 1b) [14][15][16]. Recent studies have shown that fluorinated benzimidazole
- groups have reported the direct difluoromethylation/cyclization reaction of benzimidazoles with alkenes for the syntheses of difluoromethylated tricyclic benzimidazoles to date. For example, in 2023, Chen and co-workers pioneered an electrochemical approach for the difluoromethylation and cyclization
- broader applicability in drug design to some extent. Besides, the incorporation of the PhCF2 group into tricyclic imidazoles has never been reported according to our best knowledge. Therefore, it is essential to explore environmentally friendly, cost-effective synthetic approaches for the construction of
Other Beilstein-Institut Open Science Activities
