TY - JOUR
T1 - The synthesis of pyrrolo[1,2-b][1,2,5]benzothiadiazepines from 1,2-thiazine 1-oxides - Sulfonamide analogues of the pyrrolobenzodiazepine antitumour natural products
AU - Hemming, Karl
AU - Patel, Nilesh
PY - 2004/10/4
Y1 - 2004/10/4
N2 - Pyrrolo[2,1-c][1,4]benzodiazepines (PBDs) and the corresponding pyrrolobenzothiadiazepines (PBTDs) are attractive targets as natural and synthetic antitumour antibiotics and as non-nucleosidic reverse transcriptase inhibitors. A concise synthesis of the PBTD class is presented, which starts from o-azidobenzenesulfonamide and its conversion into 2-(o- azidobenzenesulfonyl)-1,2-thiazine 1-oxides via Diels-Alder reaction. After a one-pot ring contraction, desulfurisation and aromatisation process, accompanied by concomitant same pot conversion of the azide group into a primary amine via the Staudinger reaction, these 1,2-thiazine-1-oxides yield a 1-(o-aminobenzenesulfonyl)pyrrole. N-Formylation of the amine and Bischler-Napieralski ring closure onto the pyrrole completes the PBTD synthesis.
AB - Pyrrolo[2,1-c][1,4]benzodiazepines (PBDs) and the corresponding pyrrolobenzothiadiazepines (PBTDs) are attractive targets as natural and synthetic antitumour antibiotics and as non-nucleosidic reverse transcriptase inhibitors. A concise synthesis of the PBTD class is presented, which starts from o-azidobenzenesulfonamide and its conversion into 2-(o- azidobenzenesulfonyl)-1,2-thiazine 1-oxides via Diels-Alder reaction. After a one-pot ring contraction, desulfurisation and aromatisation process, accompanied by concomitant same pot conversion of the azide group into a primary amine via the Staudinger reaction, these 1,2-thiazine-1-oxides yield a 1-(o-aminobenzenesulfonyl)pyrrole. N-Formylation of the amine and Bischler-Napieralski ring closure onto the pyrrole completes the PBTD synthesis.
KW - 1,2-Thiazine-1-oxide
KW - Azide
KW - Pyrrole
KW - Pyrrolobenzodiazepine
KW - Pyrrolobenzothiadiazepine
UR - http://www.scopus.com/inward/record.url?scp=4644228014&partnerID=8YFLogxK
U2 - 10.1016/j.tetlet.2004.08.136
DO - 10.1016/j.tetlet.2004.08.136
M3 - Article
AN - SCOPUS:4644228014
VL - 45
SP - 7553
EP - 7556
JO - Tetrahedron Letters
JF - Tetrahedron Letters
SN - 0040-4039
IS - 41
ER -