Aspects of Chemistry and Biosythesis of Opium Alkaloids

Brochmann–Hanssen, E.

doi:10.1007/978-3-642-65136-6_15

Cited by 3 publications

(4 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4) is in perfect agreement with a finding by BROCHMANN-HANSSEN et al [5]. Their results, obtained from in vivo experiments, indicate that during the early steps in papaverine formation 6-0-methylation must precede 7-0-methylation.…”

Section: Discussionsupporting

confidence: 88%

“…This means that NLS must be transformed to reticuline by three methylation reactions, two 0-methylations at positions 6 and 4' and one Nmethylation (at atom 2). Since nor-reticuline has been amply demonstrated by feeding experiments to be a precursor of reticuline in vivo [4,5], one has to assume that 0-methylation of NLS precedes N-methylation for instance in opium alkaloids. 0-Methylation of NLS is therefore an important reaction in the early steps of the biosynthesis of reticuline, the universal branch point intermediate.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Partial Purification and Properties of S-Adenosylmethionine: (R), (S)-Norlaudanosoline-6-O-Methyltransferase from Argemone platyceras Cell Cultures

1983

View full text Add to dashboard Cite

A new enzyme, S-adenosylmethionine: (R), (S)-norlaudanosoline-6-O-methyltransferase, was isolated from the soluble protein extract of A. PLATYCERAS cell cultures and purified approximately 80-fold. This enzyme catalyses the formation of 6-O-methylnorlaudanosoline, and, to a minor extent, 7-O-methylnorlaudanosoline from SAM and (S), as well as (R), norlaudanosoline. The apparent molcular weight of the enzyme is 47000 Dalton. The pH-optimum of the enzyme is 7.5, the temperature optimum, 35 degrees C. Apparent K (M) values for (S) and (R)-norlaudanosoline were 0.2 mM, and for SAM, 0.05 mM. The transferase shows high substrate specificity for tetrahydrobenzylisoquinoline alkaloids. Simple orthophenols, like phenylpropane derivatives, coumarins or flavonoids, are not accepted as substrates. The enzyme is widely distributed in benzylisoquinoline-containing plant cell cultures and is present in differentiated plants like PAPAVER SOMNIFERUM.

show abstract

Section: Discussionsupporting

confidence: 88%

Section: Introductionmentioning

confidence: 99%

Partial Purification and Properties of S-Adenosylmethionine: (R), (S)-Norlaudanosoline-6-O-Methyltransferase from Argemone platyceras Cell Cultures

1983

View full text Add to dashboard Cite

show abstract

“…316,317 Takaya and Noyori reported on the application of the Ru(II)-BINAP complexes for catalytic enantioselective hydrogenation of a wide range of (Z)-2-acyl-l-alkylidene-1,2,3,4-tetrahydroisoquinolines en route to chiral benzylated tetrahydroisoquinolines in nearly quantitative yields and high (up to >99%) optical purities, 23 setting the key stereogenic center at the C(1) position in a predictable manner. The hydrogenation products were converted by standard functional group modifications into naturally occurring isoquinoline alkaloids, like, e.g., tetrahydropapaverine, laudanosine, tretoquinol, and norreticuline.…”

Section: Ru-catalyzed Hydrogenation In Drug and Natural Product Synthmentioning

confidence: 99%

Stereoselective Hydrogenation ofCCBonds: Application to Drug and Natural Product Synthesis

Andrushko

2013

Stereoselective Synthesis of Drugs and Natural Products

View full text Add to dashboard Cite

Asymmetric homogeneous hydrogenation is perhaps one of the most researched areas in homogeneous catalysis; thus, it is now used in numerous innovative applications in stereoselective syntheses of many chiral pharmaceutical and natural products. Metal complexes, derived from transition metals, like Rh, Ru, Ir, and so on, and chiral ligands (usually mono‐ or diphosphine ligands), are widely used as catalysts in asymmetric alkene hydrogenation as a result of their efficiency in the preparation of enantiopure compounds with excellent atom economy. This chapter provides many interesting examples of homogeneous enantio‐ and diastereoselective hydrogenation of CC bonds, highlighting the utility of these methods as useful synthetic tools for the construction of stereogenic centers in stereoselective drug and natural product syntheses.

show abstract

“…Sinoacutine is further transformed to sinomenine (6) (8). There is no evidence that these reactions operate in the opium poppy (9). Consequently, the actual incorporations of the R-enantiomers in the biosyntheses are twice as great as the values reported in table 1, in which incorporations have been calculated on the basis of the racemic mixtures which were administered.…”

mentioning

confidence: 96%

Biosynthesis of Opium Alkaloids: The Effects of Structural Modification of Retieuline on Racemization and Biotransformation

Brochmann–Hanssen¹,

Cheng²,

Chiang³

1982

J. Nat. Prod.

Self Cite

View full text Add to dashboard Cite

Aspects of Chemistry and Biosythesis of Opium Alkaloids

Cited by 3 publications

References 52 publications

Partial Purification and Properties of S-Adenosylmethionine: (R), (S)-Norlaudanosoline-6-O-Methyltransferase from Argemone platyceras Cell Cultures

Partial Purification and Properties of S-Adenosylmethionine: (R), (S)-Norlaudanosoline-6-O-Methyltransferase from Argemone platyceras Cell Cultures

Stereoselective Hydrogenation ofCCBonds: Application to Drug and Natural Product Synthesis

Biosynthesis of Opium Alkaloids: The Effects of Structural Modification of Retieuline on Racemization and Biotransformation

Contact Info

Product

Resources

About