Organic & Biomolecular Chemistry
ISSN / EISSN : 1477-0520 / 1477-0539
Published by: Royal Society of Chemistry (RSC) (10.1039)
Total articles ≅ 19,560
Latest articles in this journal
Organic & Biomolecular Chemistry; https://doi.org/10.1039/d1ob01910d
One-pot synthesis of fully substituted 2-aminofurans via a Au(I)-catalyzed cascade reaction of ynamides and propargylic alcohol was realized. Hydroalkoxylation of ynamide with propargylic alcohol, Saucy-Marbet rearrangement, and cyclization of the resultant 3,4-dienamide sequentially proceeds in a one-pot reaction under highly mild conditions to give fully substituted 2-aminofurans.
Organic & Biomolecular Chemistry; https://doi.org/10.1039/d1ob01846a
An efficient gold-catalyzed oxidative cyclization of amide-alkynes is developed. A series of functionalized γ-lactams are easily accessed by employing this strategy. The tandem reaction proceeds through alkyne oxidation, carbene/alkyne metathesis, and donor/donor carbene oxidation.
Organic & Biomolecular Chemistry; https://doi.org/10.1039/d1ob01824h
A short and enantioselective synthesis of 19-epi-BE-43547 A2 chiral framework has been achieved in high yield. The challenging key C15 tertiary stereocenter was derived from D-glucose. The synthetic strategy involves a Julia-Kocienski olefination to install the lipophilic side chain. Efficient protocol for Z to E isomerization of olefin was developed using novel UV flow reactor. In addition, an unprecedented oxygen mediated hydroboration, as well as Krapcho de-carboxylation of β-keto lactone were observed.
Organic & Biomolecular Chemistry; https://doi.org/10.1039/d1ob01778k
As the common volatile precursor during the biosynthesis of trichothecenes, (−)-trichodiene (TD) is considered to be a biomarker for the respective mycotoxin content in food samples. In this work we present the syntheses of a native calibration standard and an isotope labelled derivative as internal standard for the non-invasive, on-site quantification of trichothecenes in grain bulks.
Organic & Biomolecular Chemistry; https://doi.org/10.1039/d1ob01708j
N-triflylphosphoramides (NTPA), have become increasingly popular catalysts in the development of enantioselective transformations as they are stronger Brønsted acids than the corresponding phosphoric acids (PA). Their highly acidic, asymmetric active site can activate difficult, unreactive substrates. In this review, we present an account of asymmetric transformations using this type of catalyst that have been reported in the past ten years and we classify these reactions using the enantio-determining step as the key criterion. This compendium of NTPA-catalysed reactions is organised into the following categories: 1) cycloadditions, 2) electrocyclisations, 3) addition reactions to imines, 4) electrophilic aromatic substitutions, 5) addition reactions to carbocations, 6) aldol and related reactions, 7) addition reactions to double bonds, and 8) rearrangements and desymmetrisations. We highlight the use of NTPA in total synthesis and suggest mnemonics which account for their enantioselectivity.
Organic & Biomolecular Chemistry; https://doi.org/10.1039/d1ob02000e
Herein, regioselective para-C-H halogenation of N-pyrimidyl (hetero)aromatics through SEAr (Electrophilic aromatic substitution) type reaction is disclosed. SEAr type reaction has been utilized for the C5-bromination of indolines (para-selective) with N-bromosuccinimide under metal and additive-free conditions in good to excellent yields. The developed methodology is also applicable for iodination and challenging chlorination. Pyrimidyl group is identified as a reactivity tuner which also controls the regioselectivity. The present method is also applicable for selective halogenation of aniline, pyridine, indole, oxindole, pyrazole, tetrahydroquinoline, isoquinoline, and carbazole. DFT studies such as Fukui nucleophilicity and natural charge map also supports the observed p-selectivity. Post-functionalization of the title compound into corresponding arylated, olefinated, and dihalogenated products is achieved in a one-pot, two-step fashion. Late-stage C-H bromination was also executed on drug/natural molecules (harmine, etoricoxib, clonidine, chlorzoxazone) to demonstrate the applicability of the developed protocol.
Organic & Biomolecular Chemistry; https://doi.org/10.1039/d1ob01649k
The bacterial quorum sensing (QS) system is a target for non-lethal antibacterial agents that do not encourage the development of resistance. QS inhibitors commonly contain a polar “head” moiety and a lipidic “tail” moiety. In this work, we synthesised novel QS inhibitor candidates in which the lipidic “tail” is decorated with stereospecifically positioned fluorine atoms. The presence of fluorine is shown to bias the molecules into distinctive conformations that are pre-organised for binding to the QS receptor. This translates into significant increases in QS inhibitory potency.
Organic & Biomolecular Chemistry; https://doi.org/10.1039/d1ob01313k
A low-catalyst loading Michael addition reaction of pyrazolyl nitroalkenes with 1,3-dicarbonyl derivatives has been carried out under mild reaction conditions to afford 4-substituted pyrazole derivatives in 60-87% yields and 82-96% ee. These pyrazolyl derivatives are further transformed into chiral bis-heterocyclic derivatives in up to 82% yields and up to 99% ee. The synthesized pyrazole and isoxazole based bis-heterocyclic derivatives are potential bio-active molecules expected to have significant applications. Additionally, synthesis of these bis-heterocycles can efficiently be carried out in one-pot without any loss of enantiopurity, which further adds to its significance.
Organic & Biomolecular Chemistry, Volume 19, pp 8617-8617; https://doi.org/10.1039/d1ob90150h
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