8-Hydroxy-psoralen

Fig. 3. Affinity ligand used to separate 5- and 8-hydroxy-psoralen 0-methyltransferases.

Amino acid-modified furocoumarins were prepared by condensation of the T-hydroxysuccinimide ester of 3-(2,3,5-trimethyl-7-oxofuro[3,2-g]chromen-6-yl)propanoic acid 51 with amino acids <2003JPH177>. Ethyl 3-(7-hydroxy-4-methyl-2-oxo-2/7-3-chromenyl)propanoate 49, prepared in 56% yield by Pechmann condensation of resorcinol and diethyl 2-acetylglutarate in the presence of HCl, was condensed with 3-chlorobutan-2-one in the presence of base to give propanoate 50 (Scheme 4). The MacLeod method was then used to fuse a furan ring to the benzopyran-2-one system. Heating 50 with NaOH solution (1 M) readily cyclized it into the corresponding psoralen furocoumarin 51 with simultaneous hydrolysis of the ester. 

In a search for biologically active substances from South American medicinal plants [15, 16] the roots of this plant (D. brasiliensis) were recently been reinvestigated [17] (T -hydroxy-l -methylethyl)-psoralen (11), (2 S. S R -hydroxymarmesin (12), (2 S, 3 R)-3 -... 

The substitution pattern of TfOH-mediated electrophilic aminomethylation of psoralens (furo-coumarins) by V-(hydroxymethyl)phthalimide has been elucidated <85JHC73>. Multiple phthal-imidoylated adducts were obtained when a B-ring hydroxy or methoxy activating group was present, and these resisted simple cleavage with NH2NH2. However, this two-step procedure to aminomethyl group introduction worked well when the psoralens contained only methyl substituents. 

Zou, Y, Lobera, M. and Snider, B.B. (2005) Synthesis of 2,3-dihydro-3-hydroxy-2-hydroxylalkylbenzofurans from epoxy aldehydes. One-step syntheses of brosima-cutin G, vaginidiol, vaginol, smyrmdiol, xanthoarnol, and avicenol A. Biomimetic syntheses of angelicin and psoralen.. Org. Chem., 70,1761-70. 

SYNS AMMOIDIN 6-HYDROXY-7-METHOXY-5-BENZOFURANACRYLIC ACID A-LACTONE MELADI-NIN MELADININE MELOXINE METHOXA-DOME METHOXSALEN 8-METHOXY-(FUR, NO-3, 2 il3.7-COUMARIN) 9-METHOXY-7H-FURO(3,2-g)BENZOPYRAN-7-ONE 8-METHOXY-2, 3, 6,7-FURO-COUMARIN 8-METHOXY-4, 5, 6,7-FUROCOUiMARIN 8-METHOXYPSOR. LEN 9-METHOXYPSORALEN 8-MOP 8-MP NCI-C55903 OXSORALEN OXY-PSORALEN PRORALONE-MOP... 

Hydroxylation of p-coumaric acid, followed by photocatalyzed isomerization of the double bond and lactonization, affords 7-hydroxy coumarin (umbel-liferone). Prenylation at the 6-position, epoxidation, cyclization, and a retro-aldol reaction afford the furanocoumarins (Fig. 14) some (psoralen, bergapten)... 

Oxidative processes were studied by Rodighiero et al. and Musajo et al. that showed that photolysis of psoralen and 5-methoxypsoralen (5-MOP), in water-methanol solution in the presence of flavin-mono nucleotide, leads to the formation of 6-formyl-7-hydroxycoumarin (from psoralen) and 6-formyl-7-hydroxy-5-methoxycoumarin, derived from 5-MOP. The corresponding aldehyde deriving from 8-methoxypsoralen (8-MOP) was isolated by Rodighiero et al. ... 

The same 6-formyl-7-hydroxy-8-methoxycoumarin was later characterized as a direct photolysis product of 8-MOP with the involvement of singlet oxygen, generated by the psoralen. ... 

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