Demethylierung von codein zu norcodein durch sensibilisierte photooxygenierung

Lindner, Jörg; Kuhn, Hans; Gollnick, Klaus

doi:10.1016/s0040-4039(01)84726-2

Cited by 31 publications

(10 citation statements)

References 7 publications

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“…15 Deamination and formation of carbonyl derivatives are the most common pathways. 16 Considering the singlet oxygen induced fragmentation of amino acids and possible recombination processes of the fragments, it is not surprising that compound 4 can be produced from glycine or sarcosine methyl ester. Compound 4 is very stable and has been isolated as a byproduct from similar photochemical reactions such as the reaction of C 60 with EDTA tetramethyl ester and nitrilotriacetic methyl ester.…”

Section: Resultsmentioning

confidence: 99%

“…Due to its high energy, singlet oxygen usually reacts with amine without specificity . Deamination and formation of carbonyl derivatives are the most common pathways . Considering the singlet oxygen induced fragmentation of amino acids and possible recombination processes of the fragments, it is not surprising that compound 4 can be produced from glycine or sarcosine methyl ester.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

A Novel [2 + 3] Cycloaddition Reaction: Singlet Oxygen Mediated Formation of 1,3-Dipole from Iminodiacetic Acid Dimethyl Ester and Its Addition to Maleimides

et al. 2001

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Sensitized photolysis of iminodiacetic acid methyl ester and maleimides follows a [2 + 3] cycloaddition pathway yielding pyrrolidine derivatives. This is similar to the photochemical reaction between C(60) and amines. A series of pyrrolidine derivatives are prepared by the method including multipyrrolidines from bis- and tris-maleimide starting materials. The yields range from 13% to 85%. The reaction is highly stereoselective. All the isolated products have the 1,3-dimethoxycarbonyl groups in the cis configuration. Various sensitizers may be used with slightly different yields. A plausible mechanism is proposed that involves the singlet oxygen abstraction of two alpha hydrogen atoms from the iminodiacetate and formation of a 1,3-dipole with a structure similar to the classical thermally generated 1,3-dipole.

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Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

A Novel [2 + 3] Cycloaddition Reaction: Singlet Oxygen Mediated Formation of 1,3-Dipole from Iminodiacetic Acid Dimethyl Ester and Its Addition to Maleimides

et al. 2001

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“…Amines are known quenchers of singlet oxygen, and during quenching, reaction with singlet oxygen can occur (Monroe, 1977). Oxidation to N-formyl groups (Fisch et al, 1971) and Ndemethylation (Linder et al, 1972) have been described as photooxidative reactions involving amines and singlet oxygen. Therefore, FABla (F2) and ABla (F5) could be formed in the same way.…”

Section: Discussionmentioning

confidence: 99%

Photodegradation of 4''-(epimethylamino)-4''-deoxyavermectin B1a thin films on glass

Feely¹,

Crouch²,

Arison³

et al. 1992

J. Agric. Food Chem.

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Photodegradation of 4"-(epimethylamino)-4"-deoxyavermectin Bu as thin films on glass, using artificial light, resulted in the formation of multiple photodegradates. Six primary degradates and two secondary degradates were identified. The primary degradates formed were 8,9-Z-4"-(epimethylamino)-4"deoxyavermectin Bu (a geometric isomer), delta 2,3-4"-(epimethylamino)-4"-deoxyavermectin Bu (a positional isomer), avermectin Bu monosaccharide, 4"-epiamino-4"-deoxyavermectin Bu, 4"-N-formyl-4"-deoxyavermectin Bu, and 4"-iV-methyl-N-formyl-4,,-deoxyavermectin Bu. The secondary degradates formed, both geometric isomers of two primary degradates, were 8,9-Z-4"-epiamino-4"deoxyavermectin Bu and 8,9-Z-4"-JV-formyl-4"-deoxyavermectin Bu. The substitution of the epi-iVmethylamino group for the hydroxyl group at the 4" position of avermectin Bu profoundly affected the formation of photodegradates in thin films reported in earlier studies.

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“…O-methylatheroline (67) and 10% corunnine (68). The eosine-sensitized photooxidation of 66 and dehydroglaucine (69) resulted in the formation of 67 in 85% and 76% yields, respectively, along with small quantity of 68. The 90% yield of 67 was achieved by the irradiation of norglaucine (70).…”

Section: Isoquinoline Alkaloidsmentioning

confidence: 99%

“…The Rose Bengal sensitized oxidative demethylation of codeine (173) to norcodeine (174) was achieved by Lindner et al 69 The oxygen uptake during the photooxidation of codeine was 50 times slower in ferf-butyl alcohol as compared to 2,5-dimethylfuran. Neither the A/-formyl nor the N-oxide photoproduct of 173 was isolated from the reaction mixture.…”

Section: I7i I72 VIII Opium Alkaloidsmentioning

confidence: 99%