114091-95-1Relevant academic research and scientific papers
Biosynthesis of porphyrins and related macrocycles. Part 50. Synthesis of the N-formyl-dihydro analogue of the spiro-intermediate and its interaction with uroporphyrinogen III synthase
Petersen, Paul M.,Hawker, Craig J.,Stamford, N. Patrick J.,Leeper, Finian J.,Battersby, Alan R.
, p. 1531 - 1539 (2007/10/03)
The proposed intermediacy of the spiro-system 1 for the biosynthesis of uroporphyrinogen III has focused attention on its synthesis. In this paper the approach that is explored is to carry a dihydropyrrole through the entire synthesis with the intention of converting it into a 2H-pyrrole (pyrrolenine) in one of the final steps. The chemistry of the different types of synthetic intermediates is described and also it is demonstrated that the N-formyl dihydropyrrole 37 is a strong inhibitor of cosynthetase. The conclusion is reached that of all the possible routes to the spiro-pyrrolenine 1, that via the protected dihydropyrrole 30 shows the greatest promise.
Biosynthesis of porphyrins and related macrocycles. Part 47. Synthesis and chemistry of 2H-pyrroles (pyrrolenines) related to the proposed spiro-intermediate for porphyrin biosynthesis
Hawker, Craig J.,Stark, W. Marshall,Spivey, Alan C.,Raithby, Paul R.,Leeper, Finian J.,Battersby, Alan R.
, p. 1493 - 1508 (2007/10/03)
It is proposed that the biosynthesis of uroporphyrinogen III 3, the parent precursor of the natural porphyrins, chlorins and corrins, involves a pyrrolenine 2 as a key intermediate, yet methods for the synthesis of such systems are not available. Novel routes for the synthesis of pyrrolenines by desulfurisation of unsaturated thiolactams have now been devised and the chemistry of such compounds has been explored. Enzymic experiments are carried out using a model pyrrolenine indicating that deletion of one of the pyrrole rings of the putative intermediate 2 leads to loss of tight binding.
A new procedure for the reduction of α,β-unsaturated pyrrolidinones to 2H-pyrroles and 1H-pyrroles based on initial activation by N-nitrosation
Spivey, Alan C.,Frampton, Christopher S.,Battersby, Alan R.
, p. 2103 - 2110 (2007/10/03)
A new two step procedure is developed for the half-reduction of lactams to cyclic imines and enamines. N-Nitrosation using dinitrogen tetroxide furnishes N-nitroso lactams, which undergo chemoselective 1,2-reduction to N-nitroso carbinolamines? by one equivalent of hydride delivered from lithium triethylborohydride. The nitroso group is cleaved in a novel way using samarium(II) iodide and dehydration then generates the corresponding imine (which may tautomerise to the isomeric enamine). The reduction can be performed in the presence of esters and has proved efficient for the preparation of 2H-pyrroles (pyrrolenines) and 1H-pyrroles relevant to the study of tetrapyrrole biosynthesis.
Selectivity in the Rearrangement of a Di(pyrrolylmethyl)-2H-pyrrole
Hawker, Craig J.,Stark, W. Marshall,Battersby, Alan R.
, p. 1313 - 1315 (2007/10/02)
A di(pyrrolylmethyl)-2H-pyrrole has been synthesised and its ready acid-catalysed rearrangement shows that one of the two possible modes of cleavage is preferred; this mode corresponds to that required for the formation of uroporphyrinogen-III from the putative spiro intermediate.
