1-Methylpyrrolidine-2-acetic Acid is not a Precursor of Tropane Alkaloids.

1-Methylpyrrolidine-2-acetic acid and related compounds were studied as precursors in the biosynthesis of the tropane alkaloids in Erythroxylum coca and Datura innoxia. (R,S)-[1',2-(13)C2,2-(14)C,(15)N]-1-methylpyrrolidine-2- acid, (R,S)-[1',2'-(13)C2,1'-(14)C]-1-methylpyrrolidine-2-acetic acid, (R,S) [1',2'-(13)C2,1-(14)C]-1-methylpyrrolidine-2-acetate, and (R,S)-+2'-(14)C] methylpyrrolidine-2-acetic acid N-acetylcysteamine thioester were synthesized an intact plants by leaf-planting or hydroponic-feeding. Specific incorporation of compounds into ( - )-hyoscyamine, ( - )-scopolamine, ( - )-cocaine and the biosynthetically related cuscohygrine were very low. These results indicate that 1-methylpyrrolidine acid is not an efficient precursor of tropane alkaloids.

Recent developments in the biosynthesis of the tropane alkaloids.

Recent work on the biosynthesis of the tropane moiety of cocaine, hyoscamine, scopolamine, and related alkaloids is reviewed. Revision of the generally accepted biosynthetic pathway to these alkaloids is now proposed in the light of new discoveries. New information on the biosynthesis of some of the acid moieties (benzoic, tiglic and tropic acid) of the tropane ester alkaloids is also discussed.

How I perceive and manage my illness.

The article describes some of the ongoing problems psychiatric patients encounter on a daily basis as perceived by an individual who has lived with schizophrenia for more than 25 years. Specific carefully planned coping strategies which are seen as critical to the recovery process are presented.

The treatment of schizophrenia: a patient's perspective.

The author chronicles her 20-year battle with schizophrenia and her growing acceptance of her illness. She has committed herself to leading the fullest life her disease will allow and to educating others about mental illness. While she does not deny that hospitals have their place in the treatment and stabilization of acute psychiatric problems, she believes community-based residential treatment programs are most successful in promoting long-term gains because they provide a protected yet flexible environment in which to build confidence and social skills. She believes mentally ill individuals need to be educated about their illnesses and require appropriate supportive psychotherapy, pharmacotherapy, access to support groups, and structured activities, such as working, attending school, and training for a job. She describes her own strategies for preventing relapse.

2,3-Dehydrococaine: not a direct precursor of cocaine in Erythroxylum coca.

(+/-)-3-[4(-3)H]Benzoyloxy-2-[carbonyl-13C, 14C]carbomethoxy-2-tropene (2,3-dehydrococaine) was synthesized from Ba [13C, 14C]CO3 and [4(-3)H]benzoic acid. This labeled compound (3H/14C 0.65) was administered to Erythroxylum coca plants for 3 and 15 days. After these times, cocaine was isolated and was found to have a 3H/14C ratio quite different from the administered dehydrococaine (3.0 and 10.6 for the 3- and 15-day feeding experiments, respectively). Degradations of the cocaine indicated that tritium was all located in the 4-position of its benzoyl moiety. 13C-nmr spectroscopy indicated enrichment of the carbomethoxy group of cocaine, consistent with the observed specific incorporation of the 14C. From the 3-day feeding experiment unmetabolized dehydrococaine was isolated having the same specific activity and 3H/14C ratio as the administered compound. Also from this feeding experiment 2-carbomethoxy-3-tropinone was isolated having about 1/3 the specific activity (14C) of the administered dehydrococaine and having a (-) optical rotation. These results indicate that cocaine is not formed by the direct reduction of dehydrococaine. The results indicate that cocaine is not formed by the direct reduction of dehydrococaine. The results are rationalized by proposing initial hydrolysis of the dehydrococaine to benzoic acid and 2-carbomethoxy-3-tropinone. The latter compound is then reduced to methyl ecgonine, which is then esterified with benzoic acid to yield cocaine. The change in the 3H/14C ratio is due to the fact that only the (+) enantiomer of 2-carbomethoxy-3-tropinone is converted to cocaine, and that different pool sizes of the non-labeled intermediates exist in the plant.

Synthesis of [3,5-14C]trachelanthamidine and [5-3H]isoretronecanol and their incorporation into the retronecine moiety of riddelliine in Senecio riddellii.

(+/-)-[3,5-14C]Trachelanthamidine and (+/-)-[5-3H]isoretronecanol, which are diastereomers, were prepared from potassium [14C]cyanide and [5-3H]proline, respectively. These compounds and [1,4-14C]putrescine were administered to Senecio riddellii plants resulting in the formation of labeled riddelliine, in which almost all the radioactivity was located in its retronecine moiety. The activity of the beta-alanine obtained by degradation of the retronecine was consistent with specific labeling of this pyrrolizidine base at the expected positions. The extremely high absolute incorporation (15.1, 22.1%) of trachelanthamidine into riddelliine strongly favors this 1-hydroxymethylpyrrolizidine as the one on the main biosynthetic pathway to retronecine. The lower incorporation (0.75%) of isoretronecanol may represent a minor or aberrant pathway to retronecine.