Furoxans and benzofuroxans

Cavaleiro JAS, Tome Ja PC, Faustino MAP (2007) Synthesis of Glycoporphyrins. 7 179-248 Cerecetto H, Gonzalez M (2007) Benzofuroxan and Furoxan. Chemistry and Biology. 10 265-308... 

In the following chapter, Cerecetto and Gonzalez review the classical and most modern methods of the synthesis of benzofuroxan and furoxan deriva-... 

Cerecetto H, Gonzdlez M (2007) Benzofuroxan and Furoxan. Chemistry and Biology. 1ft 265-308... 

Cerecetto, H. and Gonzdlez, M. (2007). Benzofuroxan and furoxan. chemistry and biology, bioactive heterocycles Iv (ed.) (Vol. 10, pp. 265-308) Springer Berlin/Heidelberg. 

Although benzofuroxan (Bfx) and furoxan (Fx) were first synthesized over 100 years ago, it was not until the middle of the 20th century that its relevant bioactivities were identified. Bfx s and Fx s relevant biological behaviors convert these systems in one of the most current study heterocycles in medicinal chemistry. Formally, these compounds are 1,2,5-oxadiazole hf-oxide derivatives, specifically Bfx should be named as benzo[l,2-c][l,2,5]oxadiazole 1-oxide and Fx as 1,2,5-oxadiazole 2-oxide, however, the common trivial... 

The principal methods for the construction of 1,2,5-oxadiazole frameworks were already well developed in 1984 when CHEC-I was published, and this section is therefore designed to update this coverage. Different approaches are generally required for furazans and furoxans, and furthermore the methods used for 3,4-fused arene analogues are also quite distinct. Separate sections are thus devoted to furazans, benzofurazans, furoxans, and benzofuroxans unless otherwise stated the material included is cited in the reviews listed in the Introduction to this chapter. 

Another example of ring-chain tautomerism with participation of a substituent is the interconversion of furoxan-2- and furoxan-5-oxides (104a 104b). The equilibration is presumed to proceed via an intermediate cis- 1,2-dinitrosoalkene (105). In the benzofuroxan series the involvement of the corresponding 1,2-dinitrosoarenes as intermediates has been firmly established by matrix isolation experiments (91CC1178, 91JOC5216,92CL57). 

Furazans and furoxans with a benzene ring fused at the 3- and 4-positions are generally referred to as benzofurazans (3) and benzofuroxans (4) other names include 3,4-benzo-... 

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