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20-O-Acylcamptothecin Derivatives: Evidence for Lactone Stabilization
Abstract
Convincing UV and NMR spectrophotometric evidence is presented which demonstrates that at physiological pH, 7.4, 20-O-acyl derivatives of camptothecin (CPT) are substantially more stable in the lactone form than the 20-OH parent. Additionally, it was determined by HPLC analysis that the lactone ring of a 20-O-ether derivative of CPT underwent endocyclic ring opening at pH > or =8.5, while the lactone ring of 20-O-acyl CPT derivatives remained unaffected. PEG (and other smaller alkyl) 20-O-acyl-CPT derivatives released native CPT at pH > 9.5, which arises from exocyclic cleavage, thus precluding isolation of any open CPT acyl PEG (or alkyl) carboxylate forms.
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Citations
Cited by
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Sapra, P., Zhao, H., Mehlig, M., Malaby, J., Kraft, P., Longley, C., Greenberger, L. M., & Horak, I. D. (2008) · Clinical Cancer Research · doi:10.1158/1078-0432.ccr-07-4456 · Cited by 168
Self-citationNanoconjugate formulations for enhanced drug delivery
Oner, E., Ilhan, M., Gultekin, H. E., & Karpuz, M. (2023) · Advanced and Modern Approaches for Drug Delivery · doi:10.1016/b978-0-323-91668-4.00023-x · Cited by 4
Metadata
- Authors
- Zhao, H., Lee, C., Sai, P., Choe, Y. H., Boro, M., Pendri, A., Guan, S., & Greenwald, R. B.
- Venue
- The Journal of Organic Chemistry
- Publisher
- American Chemical Society (ACS)
- Published
- 2000-06-28
- Volume
- 65
- Issue
- 15
- Pages
- 4601-4606
- ISSN
- 0022-3263 (ISSN-L)
- 1520-6904
- OpenAlex
- W2005684277
- Cited by
- 162
- References
- 0
- FWCI
- 1.58
- Type
- journal article
- Language
- en
- Open access
- closed
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- CoChat. (2026). Citation check: 20-O-Acylcamptothecin Derivatives: Evidence for Lactone Stabilization. https://app.cochat.ai/papers/10.1021/jo000221n
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- Zhao, H., Lee, C., Sai, P., Choe, Y. H., Boro, M., Pendri, A., Guan, S., & Greenwald, R. B. (2000). 20-O-Acylcamptothecin Derivatives: Evidence for Lactone Stabilization. The Journal of Organic Chemistry. https://doi.org/10.1021/jo000221n
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