Porphins synthesis

ROTHEMUND Porphine Synthesis Porphine synthesis from pyrrols and aldehydes... 

ROTHEMUND-LINDSEY PorphineSynthesis Porphine synthesis from pyrrole and aldehydes modified by Lindsey (see 1st edition). 

Excretion of uroporphin I in increased amounts and its deposition in bones and other tissues is characteristic of congenital porphyria. Turner (141) has discovered that the American fox squirrel, Sc.iurua niger, is a congential porphinuric since it excretes large quantities of uroporphin I. This animal should prove useful in a study of abnormal porphin synthesis. No evidence for a uroporphin type III has been found in nature (156). 

Porphin synthesis occurs at a rapid rate in two places, namely, in the immature red blood cell and in the etiolated plant leaf cell exposed to light. The first evidence of hemoglobin formation is observed in the polychroma-... 

Poly (vinyl pyrrol idones) polymerization, 1, 271 Polyviologens synthesis, 1, 286 Pomeranz-Fritsch synthesis isoqutnolines, 2, 428 6, 218 Pongapin synthesis, 4, 710 Poranthericine, 4, 494 ( )-Porantherine synthesis, 2, 377 Porphin, 4, 386 structure, 4, 378 Porphin, mcso-aryltri-p-tolyl-synthesis, 4, 230 Porphin, mcso-tetraalkyl-synthesis, 4, 230 Porphin, mcso-tetraaryl-synthesis, 4, 230 Porphin, mcso-tetraferrocenyl-synthesis, 4, 230 Porphin, meso-tetraphenyl-synthesis, 7, 767 Porphobilinogen biosynthesis, 1, 100... 

Synthesis of 5,10,15,20-Tetrakis(4-(polyethyleneoxy)phenyl)) porphyrin. A slurry of polyethylene methylsulfonic ester (PEvoo-OMs) (20.0 g, 69% functionalized, Mn -780 Daltons) and anhydrous cesium carbonate (CS2CO3) (9.05 g, 27 mmol) in dry toluene (75 ttiL) was prepared and to this mixture a purple solution of 5,10,15,20-tetrakis(4-hydroxyphenyl)-21H,23H-porphine (2.9 g, 4.27 mmol) in 75 mL A. A-DMF was added. The reaction mixture was warmed to 95°C with stirring for 18 hours, then the temperature increased to 130°C for a further 5 hours before coohng. The purple-brown solid was collected by filtration, washed thoroughly with methanol and dried under vacuum to yield 21.0 g of the crude ligand, h NMR (toluene-dg, 80°C) 5 8.96 (s), 8.10 (d), 7.22 (d), 4.05 (t), 1.88 (quia), 1.58 (quin.), 1.31 (br. s), 0.88 (t). 

Scheme 18.18 Synthesis of peridinin (5) [59] formation of the key building block 58 (TPP= 5,10,15,20-tetraphenyl-21 H,23H-porphin R = allyl).

The most common methods of attaching substituents to porphyrins utilize ortho-phenyl-substituted derivatives of 5,10,15,20-tetraphenyl-21 H,23//-por-phine (TPP). While (2-aminophenyl) TPP derivatives have been extensively used in the preparation of biomimetic systems,5 the corresponding (2-hy-droxyphenyl) TPP derivatives have only recently been utilized.6 One of the limitations to the use of hydroxy-substituted systems has been the synthesis of 5,10,15,20-tetrakis(2,6-dihydroxyphenyl)-21//,23//-porphine 3. 

A class of synthetic metalloporphyrins which are conveniently studied in aqueous solution derives from coordination compounds of the quadridentate ligand a,(S,7,5-tetra(4-pyridyl)-porphine. Although a method of synthesis for the zinc complex has been published,1 the yield is often poor and the method unreliable. If the same reaction is allowed to proceed under... 

The enormous amount of work on phthalocyanins1 reflects their prime importance to the dye and pigment industry and is attested to by the numerous patents in the literature. It is our experience, however, that these materials are rarely pure and that their purification, from unknown impurities, is invariably more troublesome than performing the complete synthesis. Phthalocyanins are stronger o-donors than porphines, and the former stabilize higher oxidation states of coordinated metals,2 while the tetrabenzoporphyrins have properties more characteristic of porphines. 

Streptomyces distallicus the structure elucidation and synthesis have also been made by them.165 A wide variety of porphyrins which are derivatives of porphin (125 R = H) occur in nature and exert three biological functions (a) oxygen storage and transport, as in hemoglobin, (b) cellular respiration as in the cytochromes, and (c) photosynthesis, as in the chlorophylls for detailed discussion of structures and synthesis of naturally occurring porphyrins, see references.166 Recent developments in the chemistry of polypyrrolic compounds have been reviewed.167 Several naturally occurring indole alkaloids have dimeric structures of type B,168 an example of which is c-toxiferine-I, a calabash curare alkaloid found in South American species of Strychnos.169... 

Porphyrins represent the prosthetic groups of haemo-proteins (haemoglobin, myoglobin, cytochromes, oxygenases, catalases, peroxidases, etc.). The chemical parent compound of the porphyrins is the tetranuclear pyr-rolic dye, porphin. The capacity for haem synthesis is common to almost all cells, but is especially important... 

Analogous condensations, but with a pyrrole aldehyde lead to mesomeric dipyrromethene cations, which play an important part in porphyrin synthesis. Thus, using formyldipyrromethane as the aldehyde and a second mole as the pyrrole component, with air as oxidant, porphine is formed directly, as its magnesium derivative, possibly via a dipyrromethene cationic intermediate. ... 

---