Synthesis and isolation of bromo-β-carbolines obtained by bromination of β-carboline alkaloids
β-Carbolines (1-5) undergo electrophilic aromatic substitution with N-bromosuccinimide under different experimental conditions. Although 6-bromo-nor-harmane (1a) obtained by bromination of nor-harmane (1) was isolated and fully characterized sometime ago, the other bromoderivatives of nor-harmane (1...
Guardado en:
| Autores principales: | , |
|---|---|
| Publicado: |
2001
|
| Materias: | |
| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0022152X_v38_n5_p1087_Ponce http://hdl.handle.net/20.500.12110/paper_0022152X_v38_n5_p1087_Ponce |
| Aporte de: |
| id |
paper:paper_0022152X_v38_n5_p1087_Ponce |
|---|---|
| record_format |
dspace |
| spelling |
paper:paper_0022152X_v38_n5_p1087_Ponce2023-06-08T14:46:48Z Synthesis and isolation of bromo-β-carbolines obtained by bromination of β-carboline alkaloids Ponce, María Alejandra Erra Balsells, Rosa carboline derivative reagent article bromination calculation chemical analysis chemical structure density electricity energy geometry isolation and purification purification reaction analysis β-Carbolines (1-5) undergo electrophilic aromatic substitution with N-bromosuccinimide under different experimental conditions. Although 6-bromo-nor-harmane (1a) obtained by bromination of nor-harmane (1) was isolated and fully characterized sometime ago, the other bromoderivatives of nor-harmane (1b-1e) and harmane (2a-2e) were partially described as part of the reaction mixtures. The preparation and subsequent isolation, purification and full characterization of 1b, 1c, 1d, 1e, 2a, 2b, 2c, 2d, 2e are reported (mp, Rf, 1H-nmr, 13C-nmr and ms) together with the preparation, isolation and charaterization, for the first time, of the bromoderivatives obtained from harmine (3a-3e), harmol (4a, 4b) and 7-acetylharmol (5a-5c). As brominating reagent N-bromosuccinimide and N-bromosuccinimide-silica gel in dichloromethane and in chloroform as well as the β-carboline - N-bomosuccinimide solid mixture have been used and their uses have been compared. Semiempirical AM1 and PM3 calculations have been performed in order to predict reactivity in terms of the energies of HOMO, HOMO-LUMO difference and in terms of the charge density of β-carbolines (1-5) and bromo-β-carbolines (1a-1e, 2a-2e, 3a-3e, 4a, 4b, 5a, 5b and 5c) (Scheme 1). Theoretical and experimental results are discussed briefly. Fil:Ponce, M.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Erra-Balsells, R. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2001 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0022152X_v38_n5_p1087_Ponce http://hdl.handle.net/20.500.12110/paper_0022152X_v38_n5_p1087_Ponce |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
carboline derivative reagent article bromination calculation chemical analysis chemical structure density electricity energy geometry isolation and purification purification reaction analysis |
| spellingShingle |
carboline derivative reagent article bromination calculation chemical analysis chemical structure density electricity energy geometry isolation and purification purification reaction analysis Ponce, María Alejandra Erra Balsells, Rosa Synthesis and isolation of bromo-β-carbolines obtained by bromination of β-carboline alkaloids |
| topic_facet |
carboline derivative reagent article bromination calculation chemical analysis chemical structure density electricity energy geometry isolation and purification purification reaction analysis |
| description |
β-Carbolines (1-5) undergo electrophilic aromatic substitution with N-bromosuccinimide under different experimental conditions. Although 6-bromo-nor-harmane (1a) obtained by bromination of nor-harmane (1) was isolated and fully characterized sometime ago, the other bromoderivatives of nor-harmane (1b-1e) and harmane (2a-2e) were partially described as part of the reaction mixtures. The preparation and subsequent isolation, purification and full characterization of 1b, 1c, 1d, 1e, 2a, 2b, 2c, 2d, 2e are reported (mp, Rf, 1H-nmr, 13C-nmr and ms) together with the preparation, isolation and charaterization, for the first time, of the bromoderivatives obtained from harmine (3a-3e), harmol (4a, 4b) and 7-acetylharmol (5a-5c). As brominating reagent N-bromosuccinimide and N-bromosuccinimide-silica gel in dichloromethane and in chloroform as well as the β-carboline - N-bomosuccinimide solid mixture have been used and their uses have been compared. Semiempirical AM1 and PM3 calculations have been performed in order to predict reactivity in terms of the energies of HOMO, HOMO-LUMO difference and in terms of the charge density of β-carbolines (1-5) and bromo-β-carbolines (1a-1e, 2a-2e, 3a-3e, 4a, 4b, 5a, 5b and 5c) (Scheme 1). Theoretical and experimental results are discussed briefly. |
| author |
Ponce, María Alejandra Erra Balsells, Rosa |
| author_facet |
Ponce, María Alejandra Erra Balsells, Rosa |
| author_sort |
Ponce, María Alejandra |
| title |
Synthesis and isolation of bromo-β-carbolines obtained by bromination of β-carboline alkaloids |
| title_short |
Synthesis and isolation of bromo-β-carbolines obtained by bromination of β-carboline alkaloids |
| title_full |
Synthesis and isolation of bromo-β-carbolines obtained by bromination of β-carboline alkaloids |
| title_fullStr |
Synthesis and isolation of bromo-β-carbolines obtained by bromination of β-carboline alkaloids |
| title_full_unstemmed |
Synthesis and isolation of bromo-β-carbolines obtained by bromination of β-carboline alkaloids |
| title_sort |
synthesis and isolation of bromo-β-carbolines obtained by bromination of β-carboline alkaloids |
| publishDate |
2001 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0022152X_v38_n5_p1087_Ponce http://hdl.handle.net/20.500.12110/paper_0022152X_v38_n5_p1087_Ponce |
| work_keys_str_mv |
AT poncemariaalejandra synthesisandisolationofbromobcarbolinesobtainedbybrominationofbcarbolinealkaloids AT errabalsellsrosa synthesisandisolationofbromobcarbolinesobtainedbybrominationofbcarbolinealkaloids |
| _version_ |
1768543310677278720 |