Results 21 to 30 of about 428 (148)

2-Alkyl-4-oxohexahydropyrimido[4,5-d]- and -[5,4-d]azocines

, 2020
It has been established that 2-R-4-oxotetrahydropyrido[4,3-d]pyrimidines, under the action of activated alkynes in methanol, form a mixture of 2-R-4-oxohexahydropyrimido[4,5-d]azocines and products of decomposition of the tetrahydropyridine ring, the 2-R-
Ovcharov M.V., Kulikova L.N., Borisov R.S., Borisova T.N., Varlamov A.V., Voskressensky L.G., Listratova A.V.   +6 more
core   +2 more sources

Helically Chiral π‐Expanded Azocines Through Regioselective Beckmann Rearrangement and Their Charged States

Angewandte Chemie, Volume 136, Issue 29, July 15, 2024.
Regioselective Beckmann rearrangement allowed for convenient synthesis of negatively curved π‐expanded [6]helicenes with integrated azocine units. The helical compounds display high configurational stability and distinct homoenantiomeric π‐ π stacking in the solid state. Amphoteric two electron redox chemistry allows for characterization of the charged
Jan Borstelmann, Lars Schneider, Frank Rominger, Felix Deschler, Milan Kivala   +4 more
wiley   +2 more sources

Tetrahydropyridine (THP) ring expansion under the action of activated terminal alkynes. The first synthesis and X-ray crystal structure of tetrahydropyrimido[4,5-d]azocines

, 2020
Tetrahydropyridopyrimidines (THPPm) 1-3 underwent tandem cleavage-cyclization piperidine ring enlargement under the action of terminal activated alkynes to produce tetrahydropyrimido[4,5-d]azocines 4-7 in good preparative yields. The latter compounds are
Kostenev I.S., Kulikova L.N., Borisova T.N., Varlamov A.V., Voskressensky L.G.   +4 more
core   +2 more sources

Synthesis of Benzo[b]azocin‐2‐ones by Aryl Amination and Ring‐Expansion of α‐(Iodophenyl)‐β‐oxoesters

Chemistry – A European Journal, Volume 25, Issue 65, Page 14912-14920, November 22, 2019., 2019
Expanding rings: A sequence of aryl amination of α‐(iodophenyl)‐β‐oxoesters followed by ring transformation is the key to accessing hexahydrobenzo[b]azocin‐2‐on‐6‐carboxylic esters. Abstract Transformation of β‐oxoesters with PhI(OCOCF3)2 leads to α‐(ortho‐iodophenyl)‐β‐oxoesters.
Anna Dierks, Jan Tönjes, Marc Schmidtmann, Jens Christoffers   +3 more
wiley   +1 more source

18F‐Labeling Using Click Cycloadditions

BioMed Research International, Volume 2014, Issue 1, 2014., 2014
Due to expanding applications of positron emission tomography (PET) there is a demand for developing new techniques to introduce fluorine‐18 (t1/2 = 109.8 min). Considering that most novel PET tracers are sensitive biomolecules and that direct introduction of fluorine‐18 often needs harsh conditions, the insertion of 18F in those molecules poses an ...
Kathrin Kettenbach, Hanno Schieferstein, Tobias L. Ross, Olaf Prante   +3 more
wiley   +1 more source

The first synthesis of 6-(phenylethynyl)-substituted tetrahydroazocino[5,4-b]indoles

, 2020
The reaction of 2-methyl-1-(phenylethynyl)-2,3,4,9-tetrahydro-1?-β-carboline with activated alkynes in acetonitrile led to the formation of 1-vinyl-substituted β-carbolines and condensed azocines.
Titov A.A., Borisov R.S., Kulikova L.N., Varlamov A.V., Voskressensky L.G., Kobzev M.S., Samavati R.   +6 more
core   +2 more sources

The first synthesis and X-ray crystal structure of tetrahydropyrrolo[2,3-d]azocines

, 2020
Tetrahydropyrrolo[3,2-c]pyridines (THPP) upon the reaction with DMAD in acetonitrile or DMSO at rt underwent ring expansion, affording tetrahydropyrrolo[2,3-d]azocines; these latter compounds have not previously been reported in the literature.
Chernyshev A.I., Soklakova T.A., Alexandrov G.G., Kulikova L.N., Varlamov A.V., Borisova T.N., Voskressensky L.G.   +6 more
core   +1 more source

Modifications of Prenyl Side Chains in Natural Product Biosynthesis

Angewandte Chemie International Edition, Volume 63, Issue 52, December 20, 2024.
This review summarizes the unique modifications of prenyl side chains involved in natural product biosynthesis, including epoxidation, dehydrogenation, oxidation of methyl groups to carboxyl groups, C−C bond cleavage and oxidative cyclization. Abstract In recent years, there has been a growing interest in understanding the enzymatic machinery ...
Huibin Wang, Yi Yang, Ikuro Abe
wiley   +1 more source

Synthesis of benzoazocines from substituted tetrahydroisoquinolines and activated alkynes in a tetrahydropyridine ring expansion

, 2020
Tetrahydroisoquinolines underwent tandem piperidine ring enlargement in the presence of activated alkynes in acetonitrile or methanol, producing tetrahydrobenzo[d]azocines in high yields. © Wiley-VCH Verlag GmbH & Co.
Alexandrov G.G., Borisova T.N., Varlamov A.V., Voskressensky L.G., Listratova A.V.   +4 more
core   +2 more sources

Suppressing Inversion of a Chiral Polycyclic Aromatic Aza Monkey Saddle by Molecular Editing

Helvetica Chimica Acta, Volume 107, Issue 12, December 2024.
Abstract Chiral polycyclic aromatic hydrocarbons with monkey saddle topology are a fascinating class of negatively curved compounds. To make the monkey‐saddles valuable building blocks for chirality‐assisted synthesis (CAS) approaches, the inversion barriers between the two possible enantiomers need to be high enough to prevent interconversion under ...
Tobias Kirschbaum, Simone Felicia Ebel, Frank Rominger, Michael Mastalerz   +3 more
wiley   +1 more source