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Search for "release" in Full Text gives 587 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Configuration–packing synergy enabling integrated crystalline-state RTP and amorphous-state TADF
Beilstein J. Org. Chem. 2026, 22, 224–236, doi:10.3762/bjoc.22.16
- . On the other hand, the small ΔEST plays a critical role in facilitating the RISC process, as it lowers the thermal activation barrier between the S1 and T1 states. This small energy gap makes it easier for the T1 to upconvert to the S1 through the RISC process, resulting in the release of energy in
Synthesis of diaryl phosphates using phytic acid as a phosphorus source
Beilstein J. Org. Chem. 2026, 22, 213–223, doi:10.3762/bjoc.22.15
- condense into a myo-inositol skeleton. Phytic acid can be enzymatically hydrolyzed in the presence of phytases, resulting in the release of phosphoric acid molecules [3][4][5]. Plants and microorganisms possess their own phytases and thus utilize phytic acid as a phosphorus source. However, the artificial
- gives a lower yield because the phytic acid forms a syrup-like precipitate in the reaction mixture due to its poor solubility in organic solvents, thereby preventing efficient release of phosphoric acid into the reaction mixture. The plot depicted in Figure 4 shows that there is almost no induction
Sustainable electrochemical synthesis of aliphatic nitro-NNO-azoxy compounds employing ammonium dinitramide and their in vitro evaluation as potential nitric oxide donors and fungicides
Beilstein J. Org. Chem. 2025, 21, 2739–2754, doi:10.3762/bjoc.21.211
- -nitrosopropane (1a) is expected to be barrierless with the formation of N-oxyl radical B. The radical B undergoes very low-barrier (ΔG≠ 5.5 kcal/mol) fragmentation with the release of NO2 molecule and formation of the final product 2a. An alternative pathway for the formation of 2a is a direct NO2 extrusion from
- synthesized nitro-NNO-azoxy compounds were tested for fungicidal activity against phytopathogenic fungi and for NO-release activity. Earlier we have demonstrated [87] that nitro-NNO-azoxy arenes were discovered as a novel class of fungicides, with in vitro activity against a broad range of phytopathogenic
- investigated an ability to release NO for the synthesized aliphatic nitro-NNO-azoxy compounds (Figure 4). Well-known NO-donor compounds 3-carbamoyl-4-(hydroxymethyl)furoxan (CAS-1609) [100][101] and nitroglycerin (NG) [102] were used as reference agents. The NO2− assumed to be formed as a result of NO
Mechanistic insights into hydroxy(tosyloxy)iodobenzene-mediated ditosyloxylation of chalcones: a DFT study
Beilstein J. Org. Chem. 2025, 21, 2703–2715, doi:10.3762/bjoc.21.208
- HTIB attacks at the α-position resulting in release of IPh from Int3. This attack would lead to the formation of α,β-ditosyloxy ketones (vicinal product) (Scheme 4). It is evident from the comparison between reaction profiles shown in Figure 6 and Figure 7 vis-à-vis reaction profile shown in Figure 2
Silica gel with covalently attached bambusuril macrocycle for dicyanoaurate sorption from water
Beilstein J. Org. Chem. 2025, 21, 2604–2611, doi:10.3762/bjoc.21.201
- release any BU1 and therefore, the macrocycle is indeed covalently bound in the SG-NHCO-BU1 material. This is in contrast with the SG-BU1 material, which released BU1 to the KOH solution as evidenced by marked changes of dicyanoaurate in its absorption spectra (Figure 1C). A potential application of these
- presence of salt showing it is suitable for applications in an aqueous environment. SG-BU1 proved to be stable in chloroform, dichloromethane, and methanol even after addition of TBACl or NaCl, respectively. We did not detect any release of BU1 from SG-BU1 in aqueous phosphate buffer by NMR, but we
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
- activities and serves as a potent modulator of intracellular calcium release channels. In contrast to ryanodol (4), compound 1 possesses a pyrrole-2-carboxylate ester moiety at the C3 position. This ester group can be cleaved via hydrolysis to yield 4. However, the reverse transformation – the synthesis of
- )allylium tetrafluoroborate, which was then coupled to the C3 hydroxy group via Yamaguchi esterification. Global deprotection subsequently afforded ryanodine (1) in 10 steps, thus achieving this critical synthetic transformation. Although the interaction of ryanodine with intracellular calcium release
Effect of a photoswitchable rotaxane on membrane permeabilization across lipid compositions
Beilstein J. Org. Chem. 2025, 21, 2498–2512, doi:10.3762/bjoc.21.192
- modulate membrane permeability in large unilamellar vesicles (LUVs) of varying lipid compositions. Upon photoisomerization, the rotaxane significantly enhanced the release of the hydrophilic dye sulforhodamine B in vesicles composed of EYPC/Chol 8:2, with release increasing from 29% (non-irradiated) to 59
- % (irradiated). Moreover, gel-phase DPPC bilayers also exhibited an increase in release from 7% to 14%. On the contrary, highly fluid pure EYPC bilayers showed high baseline release upon rotaxane incorporation (64%), with photoswitching producing only a slight increase (70%), as most dye was released within the
- first minutes of rotaxane insertion. Likewise, azobenzene photoswitching did not induce permeabilization in the more rigid and thicker EYPC/Chol 6:4 bilayers, which showed minimal release (5%). Furthermore, we discovered that when the unthreaded axle is irradiated with light, an unknown, irreversible
Assembly strategy for thieno[3,2-b]thiophenes via a disulfide intermediate derived from 3-nitrothiophene-2,5-dicarboxylate
Beilstein J. Org. Chem. 2025, 21, 2489–2497, doi:10.3762/bjoc.21.191
- reaction conditions to release thiolate species capable of reacting separately with ester 1 to form compound 2. Disulfide 3 was found to be an accessible and stable precursor of dimethyl 3-mercaptothiophene-2,5-dicarboxylate, a molecule that is suitable for S-alkylation. In this regard, reductive cleavage
Synthesis of the tetracyclic skeleton of Aspidosperma alkaloids via PET-initiated cationic radical-derived interrupted [2 + 2]/retro-Mannich reaction
Beilstein J. Org. Chem. 2025, 21, 2470–2478, doi:10.3762/bjoc.21.189
- leads to ketene D, which can undergo cycloaddition with an alkene to yield E. This fragmentation pathway dominates under various conditions (e.g., transition-metal catalysis, nucleophilic addition) and is driven by ring-strain release [11]. PET, an alternative to direct excitation and EnT, enables the
- generates the cationic radical G, which initiates formation of H, which has a strained bicyclo [3.2.0]heptane core. Strain release of H triggers a downstream radical-driven retro-Mannich reaction, which ultimately results in the formation of J via reductive quenching of intermediate I. As part of our
- intermediacy of IN4 was ruled out. We assume that the overlap between the sp2-hybridized N spin center and σ* (C19–C3) in TS2, and the ring-strain release of the transient bicyclo[2.2.0]hexane unit, play essential roles that enable the reaction to occur. Thus, natural bond orbital (NBO) [33] and Mayer bond
Ex-situ generation of gaseous nitriles in two-chamber glassware for facile haloacetimidate synthesis
Beilstein J. Org. Chem. 2025, 21, 2465–2469, doi:10.3762/bjoc.21.188
- is not easily done as the system is now under pressure. The chamber was then opened to release excess gas (on small scale) and the product in chamber B can be obtained by concentration and purification. The use of other bases than DBU, was also investigated. Similar to the synthesis of
Rotaxanes with integrated photoswitches: design principles, functional behavior, and emerging applications
Beilstein J. Org. Chem. 2025, 21, 2345–2366, doi:10.3762/bjoc.21.179
- for drug delivery, therapeutics, and various biotechnological applications [85][86][87][88]. As a proof of principle, this rotaxane was used to trigger the light-induced release of hydrophilic cargo from large vesicles, highlighting its potential as a platform for controlled drug delivery. Recently
- photoswitchable rotaxanes into lipid membranes has revealed exciting opportunities for future biooriented applications. These applications include light-controlled systems for drug release, ion transport, rotaxane-based therapeutics, and molecular tools capable of modulating biological processes in living cells
Comparative analysis of complanadine A total syntheses
Beilstein J. Org. Chem. 2025, 21, 2334–2344, doi:10.3762/bjoc.21.178
- underwent ketone release and amine-ketone condensation to form iminium ion 27. Under the same acidic conditions, enamide 26 underwent hydrolysis and tautomerization to form enol 28. Conjugate addition of enol 28 to iminium ion 27 gave 29 for the subsequent intramolecular Mannich cyclization to deliver 30
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
- ingeniously leverages the high selectivity of photochemical reactions and the strain-release property of rearrangement reactions, enabling the precise construction of multiple stereocenters in one step and overcoming the synthetic challenges posed by contiguous quaternary carbon centers and sterically
- Norrish–Yang cyclization, followed by a strain-release Pd-catalyzed C–C cleavage/cross-coupling protocol [9][11]; the strategy was subsequently applied to the total synthesis of lycoplatyrine A (89) in 2021 [38]. Isolated by Low’s group [39], lycoplatyrine A (89) belongs to the lycodine-type Lycopodium
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
- elastase release and superoxide-anion generation. In 2024, Baudoin and co-workers presented an efficient route for the first total synthesis (+)-randainin D (13) by utilizing an early-staged Ru-catalyzed desymmetric enantioselective reduction as the key transformation [53]. As shown in Scheme 5 [53], based
Solar thermal fuels: azobenzene as a cyclic photon–heat transduction platform
Beilstein J. Org. Chem. 2025, 21, 2036–2047, doi:10.3762/bjoc.21.159
- comparisons highlight future directions for cross-material integration. The reversible trans–cis isomerization of azobenzene makes it an ideal model system for studying solar thermal fuels, as it enables both solar energy storage and heat release. While significant advances have been made, critical challenges
- , and hinders practical deployment. Third, azobenzene groups release energy through a process involving thermal relaxation or thermally induced cis–trans isomerization. Temperature critically governs the efficiency and kinetics of this process: elevated temperatures accelerate uncontrolled instantaneous
- heat release, while low temperatures induce phase transition-induced failures that compromise structural stability. Despite tunable photothermal parameters, achieving controlled heat release and structural robustness under extreme temperatures remains a pivotal challenge for azobenzene systems. Looking
Understanding the origin of stereoselectivity in the photochemical denitrogenation of 2,3-diazabicyclo[2.2.1]heptene and its derivatives with non-adiabatic molecular dynamics
Beilstein J. Org. Chem. 2025, 21, 2007–2020, doi:10.3762/bjoc.21.156
- been employed to release carbon monoxide at relatively safer doses in biological systems using photoresponsive CO-releasing molecules (photo-CORMs) [4] because these have shown anti-inflammatory activity [5][6]. Photochemical denitrogenation of azoalkanes has been utilized in the stereoselective
Chiral phosphoric acid-catalyzed asymmetric synthesis of helically chiral, planarly chiral and inherently chiral molecules
Beilstein J. Org. Chem. 2025, 21, 1864–1889, doi:10.3762/bjoc.21.145
- inherently chiral eight-membered azaheterocycles 72 with moderate to good enantioselectivity, along with the release of CO2 (Scheme 20). While the enantioselectivity using certain substrates was initially unsatisfactory, simple phase separation significantly enhanced the enantiopurity of the products by
- 71 yielded the cyclic intermediate INT-B, which then underwent addition with aniline co-catalyst 73 to form INT-C. The CPA-enabled release of CO2 from INT-C yielded the imine-containing intermediate INT-D, which underwent iterative addition with INT-B, followed by release of CO2 to afford INT-E. The
Photoswitches beyond azobenzene: a beginner’s guide
Beilstein J. Org. Chem. 2025, 21, 1808–1853, doi:10.3762/bjoc.21.143
Research progress on calixarene/pillararene-based controlled drug release systems
Beilstein J. Org. Chem. 2025, 21, 1757–1785, doi:10.3762/bjoc.21.139
- Liu-Huan Yi Jian Qin Si-Ran Lu Liu-Pan Yang Li-Li Wang Huan Yao School of Pharmaceutical Science, Hengyang Medical School, University of South China, Hengyang 421001, China 10.3762/bjoc.21.139 Abstract Intelligent controlled-release drug delivery systems that are responsive to various external
- release systems based on host–guest selective recognition, self-assembly, and nano-valves by the use of of calixarenes and pillararenes from five perspectives: pH, light, enzyme, hypoxia, and multi-stimuli combination responses. Furthermore, the article projects the future clinical application prospects
- of controlled-release technologies, with the aim of offering a reference for the utilization of aromatic macrocycles in drug-controlled release applications. Keywords: aromatic macrocycle; controlled-release drug delivery systems; stimulus response; supramolecular chemistry; Introduction Drugs are
Continuous-flow-enabled intensification in nitration processes: a review of technological developments and practical applications over the past decade
Beilstein J. Org. Chem. 2025, 21, 1678–1699, doi:10.3762/bjoc.21.132
- (e.g., safety) and fundamental challenges (e.g., mass/heat transfer limitations). Process safety assessment: Nitration reactions pose significant safety risks due to their highly exothermic nature (ΔH ≈ −73 to −253 kJ/mol) [35], which can trigger thermal runaway if heat release is uncontrolled, and the
- the material [70]. Oxygen balance (OB), a critical parameter quantifying how well an explosive provides its own oxidant, reveals potential safety risks when OB values exceed the threshold of −200. Since the energy release predominantly originates from oxidation reactions, the available oxygen content
- in a nitric acid/acetic anhydride system under semi-batch conditions, revealing an average reaction enthalpy of −173.63 kJ·mol−1 – significantly more exothermic than conventional nitration processes, with this enhanced exothermicity likely arising from concurrent heat release during acetic anhydride
Chemical synthesis of glycan motifs from the antitumor agent PI-88 through an orthogonal one-pot glycosylation strategy
Beilstein J. Org. Chem. 2025, 21, 1587–1594, doi:10.3762/bjoc.21.122
- antitumor agent PI-88 (muparfostat), which retards tumor growth via inhibiting angiogenesis in two ways: 1) interaction with pro-angiogenic growth factors such as vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF) and 2) by prevention of the release of angiogenic growth factors
Highly distinguishable isomeric states of a tripodal arylazopyrazole derivative on graphite through electron/hole-induced switching at ambient conditions
Beilstein J. Org. Chem. 2025, 21, 1496–1507, doi:10.3762/bjoc.21.112
- switches with multiple states [3], logic-in-memory operations using single-metallofullerenes [4], multistate molecular switches [5], molecular memory and logic processing based on guest capture/release [6], etc., have demonstrated the possibility of using single molecules in logic operations. Manipulating
N-Salicyl-amino acid derivatives with antiparasitic activity from Pseudomonas sp. UIAU-6B
Beilstein J. Org. Chem. 2025, 21, 1388–1396, doi:10.3762/bjoc.21.103
- released by microorganisms into their surrounding extracellular environment to chelate iron and selectively import it into the microbial cells [12][13]. It has been suggested that the release of siderophores by soil-dwelling pseudomonads give them an ecological edge by creating an iron-deprived environment
- ]. The biosynthetic route of compound 1 leads to the amide-bond formation step between the PmsG-tethered threonine and salicylic acyl group leading to intramolecular dehydration. The decarboxylated product of histidine, histamine serves as a nucleophilic substrate to release the corresponding uncyclised
Oxetanes: formation, reactivity and total syntheses of natural products
Beilstein J. Org. Chem. 2025, 21, 1324–1373, doi:10.3762/bjoc.21.101
- 175 in a divergent synthesis of 3,3-disubstituted oxetane amino esters 176 based on a facile, strain-release-driven Giese addition of nitrogen- or oxygen-stabilised radicals (Scheme 44) [96]. The radicals were generated through a photochemical oxidative decarboxylation of amino- or alkoxycarboxylic
Recent advances in amidyl radical-mediated photocatalytic direct intermolecular hydrogen atom transfer
Beilstein J. Org. Chem. 2025, 21, 1306–1323, doi:10.3762/bjoc.21.100
- radical anion 15 was reduced by the photocatalyst Ir(Fppy)3 from the reagent 11. The resulting anion 14 underwent aromatization to release a nitrile anion, subsequently yielding product 12. This strategy also successfully produced products 16 and 17 with yields of 85% and 56%, respectively, from
- able to abstract a hydrogen atom from substrate 1. The addition of the corresponding radical 4 to HRP-5 facilitated the release of amidyl radical 36, which simultaneously produced the final product 35. Amidyl radical 36 was capable of abstracting hydrogen atoms from both substrate 1 and AQ–H. The HAT
- radical 47 can be intercepted by species 43, simultaneously releasing radical 48 and product 44. Radical 48 reacts with HRP-6, leading to the regeneration of amidyl radical 45, the release of byproduct 49, and the initiation of a chain reaction pathway. Notably, this system could give rise to the
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