624-75-9Relevant articles and documents
Methyl Radical Initiated Kharasch and Related Reactions
Tappin, Nicholas D. C.,Renaud, Philippe
supporting information, p. 275 - 282 (2020/12/07)
An improved procedure to run halogen atom and related chalcogen group transfer radical additions is reported. The procedure relies on the thermal decomposition of di-tert-butylhyponitrite (DTBHN), a safer alternative to the explosive diacetyl peroxide, to produce highly reactive methyl radicals that can initiate the chain process. This mode of initiation generates byproducts that are either gaseous (N2) or volatile (acetone and methyl halide) thereby facilitating greatly product purification by either flash column chromatography or distillation. In addition, remarkably simple and mild reaction conditions (refluxing EtOAc during 30 minutes under normal atmosphere) and a low excess of the radical precursor reagent (2 equivalents) make this protocol particularly attractive for preparative synthetic applications. This initiation procedure has been demonstrated with a broad scope since it works efficiently to add a range of electrophilic radicals generated from iodides, bromides, selenides and xanthates over a range of unactivated terminal alkenes. A diverse set of radical trap substrates exemplifies a broad functional group tolerance. Finally, di-tert-butyl peroxyoxalate (DTBPO) is also demonstrated as alternative source of tert-butoxyl radicals to initiate these reactions under identical conditions which gives gaseous by-products (CO2). (Figure presented.).
ANTHARQUINONE COMPOUNDS AS ANTI CANCER COMPOUNDS
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Page/Page column 15, (2008/06/13)
Anthraquinone compounds of the general formula (I) or a salt thereof (Formula I) in which R1 to R4 are each selected from the group consisting of H, C1-4 alkyl, X1, -NHR0N (R5)2 in which R0 is a C1-12 alkanediyl and each R5 is H or optionally substituted C1-4 alkyl, and a group of formula (II) in which at least one of R6,R7 and R8 is selected from X2 , and X2 substituted C1-4 alkyl and any others are H or C1-4 alkyl; R9 is selected from H, C1-4 alkyl, X2 and X2 substituted C1-4 alkyl; m is 0 or 1; n is 1 or 2; X1 is a halogen atom, a hydroxyl group, a C1-6 alkoxyl group, an aryloxy group or an acyloxy group; and X2 is a halogen atom, a hydroxyl group, a C1-6 alkoxyl group, an aryloxy group or an acyloxy group; provided that at least one of R1 to R4 is a group of formula (II). The N-oxides are useful prodrugs which are selectively bioreduced in hypoxic tumours to the corresponding cyclic amine derivatives. The amine compounds are cytotoxic and may be used as alkylating agents having topoisomerase II inhibiting activities in cancer therapy.
Bridged-ring Nitrogen Compounds. Part 9. Use of a Ring-expansion Reaction for the Synthesis of 1,5-Methano-4-benzazonin-12-ones and Derivatives of Benzocycloheptapyrrole.
McKay, Roslyn,Proctor, George R.,Scopes, David I. C.,Sneddon, Andrew H.
, p. 2024 - 2055 (2007/10/02)
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