7688-64-4Relevant academic research and scientific papers
An alternative preparation of camptothecin 20(S)-acetate
Cao, Zhisong
, p. 2013 - 2019 (1997)
Camptothecin 20(S) acetate was obtained in 60% yield by reaction of camptothecin with trichloroethane in sulfuric acid. This method represents another alternative preparation of camptothecin ester using trichloroethane as acylating agent.
Acetylation of Camptothecins Using Lithium Bromide as Catalyst
Ravindranath,Ramesh,Reddy, M. Ravinder,Srinivas,Das, Biswanath
, p. 4029 - 4035 (2003)
Camptothecin and 9-Methoxycamptothecin, two promising naturally occurring anticancer alkaloids containing a tertiary hydroxy group, were acetylated with acetic anhydride at room temperature in the presence of lithium bromide as catalyst. The similar method was followed for acetylation of other two related natural alkaloids, mappicine and 9-methoxymappicine.
Preparation of 14-nitrocamptothecin derivatives by reactions of camptothecin with nitronium tetrafluoroborate in acidic solvents
Cao, Zhisong
, p. 2629 - 2632 (1996)
The new camptothecin derivatives (20S)-20-O-acetyl-14-nitrocamptothecin 7 and 5-hydroxy-14-nitrocamptothecin 8 are prepared by the reactions of camptothecin 1 with nitronium tetrafluoroborate 9 in acetic anhydride and trifluoroacetic acid, respectively. When acetic acid is used as reaction solvent, the esterification product (20S)-20-O-acetylcamptothecin 6 is obtained.
Methods Of Making Esters Of Camptothecins
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Page/Page column 6-7, (2008/06/13)
Methods of preparing CPT-esters are described. The methods include using at least one acid in the esterification reactions or acylation reactions of camptothecins.
Copper(I) iodide-promoted hydroxylation onto the lithium or potassium enolate of lactones and lactams
Nakazawa, Norio,Tagami, Keiko,Iimori, Hitoshi,Sano, Shigeki,Ishikawa, Tsutomu,Nagao, Yoshimitsu
, p. 2157 - 2170 (2007/10/03)
After enolization of lactones (1a,b) and lactams (2a,b) with lithium or potassium hexamethyldisilazide in THF, each resultant enolate was treated with a solution prepared by mixing copper(I) iodide, pyridine, and tert-butyl hydroperoxide or N-methylmorpho
Studies on phytochemicals : Part XV -Investigation on the alkaloidal constituents of Indian Mappia foetida
Das, Biswanath,Rao, S. Padma,Kashinatham, A.,Srinivas, K. V. N. S.
, p. 208 - 210 (2007/10/03)
Three antitumour alkaloids, camptothecin (1), 9-methoxycamptothecin (2) and 20-O-acetylcamptothecin (3) have been isolated from the stems of Indian Mappia foetida. The presence of 3 in this indigenous species is reported for the first time. The 13C NMR spectra of the alkaloids 2 and 3 have been studied. The effects of different solvent systems and the variation of temperature on the 1H NMR spectra of these compounds (1-3) have been discussed.
Camptothecin derivatives and process for preparing same
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, (2008/06/13)
New Camptothecin derivatives possessing high anti-tumor activity with slight toxicity, represented by the general formula: STR1 wherein R1 is a hydrogen atom, an alkyl group, a hydroxyl group, an alkoxy group or an acyloxy group, R2 for a hydrogen atom, an alkyl group, an aralkyl group, a hydroxymethyl group, a carboxymethyl group or an acyloxymethyl group, and R3 is the grouping --XR' (where R' is a hydrogen atom, an alkyl group or an acyl group and X is an oxygen atom or a sulfur atom), a nitro group, an amino group, an alkylamino group, an acylamino group or a halogen atom, with the proviso that when both of R1 and R2 are hydrogen atoms, R3 should not be a hydroxyl group, methoxy group or acetoxy group. These new camptothecin derivatives are prepared by treating a 5-R1 -7-R2 -camptothecin derivative with a peroxidant and then reacting the resultant 5-R1 -7-R2 -camptothecin-1-oxide with an active hydrogen compound under irradiation of UV-rays or by catalytically hydrogenating the ring B of camptothecin in a solvent, treating the resultant tetrahydro product with an acylating agent, introducing a nitro group into the 10-position of the acylated product by the reaction with nitric acid, splitting off the acyl group in the 10-nitro product by hydrolysis and treating the hydrolyzed tetrahydro product with an oxidizing agent for dehydrogenation, and if desired, reducing the nitro group in the resulting product to an amino group and modifying the amino group by N-alkylation, N-acylation or by diazotization followed by hydrolysis or the Sandmeyer reaction, before or after the oxidation of the 10-nitro-tetrahydro product.
