2/f-l-Benzopyrans

C9H5NO4 Oximidobenzotetronic acid (3-Nitroso-4-hydroxycoumarin) (2/f-l-Benzopyran-2,3,4-trione 3-oxime) Gravimetric MetaUochromic indicator Separation and determination Spectrophotometric Spot test Fe Fe Pd, Ru Cu, Ir, Os, Pt, Th Co, Cu, Fe 85-90... 

Figure 3.21. 2/f-l-benzopyrans with novel substitution at the 2-position. 

Labsky et have studied the photochromic behaviour of spiropyrans. For example, r,3, 3 -trimethyl-6-nitrospiro(2/f-l-benzopyran-2,2 -indoline) undergoes the configurational change shown in Scheme 12. 

Evans, J.M., Fake, C.S., Hamilton, T.C., Poyser, R.H. and Watts, E.A. (1983) Synthesis and antihypertensive activity of substituted trans-4-amino-3,4-dihydro-2,2-dimethyl-2/f-l-benzopyran-3-ols. J. Med. Chem. 26 1582-1589. 

Dihydro-5,7-dihydroxy-3-(2,4-dihydroxyphenyl)-6-(3-methyl-2-butenyl)-2/f-l-benzopyran, see T-10068... 

Guillaumet, G. Determination of (3-cyclodextrin inclusion complex constants for 3,4-dihydro-2-/f-l-benzopyran enan- 17. 

Or the obtained hydroxyketone should be (II). This appears confirmed later on by obtaining 6-bromo-3,4-dihydro-2,2,7-trimethyl-2/f-l-benzopyran-4-one with this hydroxyketone [2515]. 

Demir AS, Tanyeli C, GKlbeyaz V, AkgKn H. Enantioselec-tive synthesis of 4-hydroxy-3-(3-oxo-l-phenyl butyl)-2/f-l-benzopyran-2-one (warfarin). Turk. J. Chem. 1996 20(2) 139-145. 

Methyl-2/f-l-benzopyran-2-one, M-00141 Methylcalcein blue, M-00153 Methylcalcein Di-Na salt, in M-00152... 

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