How does paynantheine relate structurally to mitragynine?

Both belong to the corynantheine subclass of indole alkaloids and share the core indole framework. They differ in specific substituents and stereochemistry.

Is paynantheine quantified on a Certificate of Analysis?

It can be. Many COAs for kratom and 7-OH products report paynantheine as a percent-assay value alongside mitragynine and 7-OH, particularly for products standardized to a specific alkaloid profile.

Alkaloids & Chemistry

Paynantheine

At-a-glance comparison

Spec	Value
Compound class	Indole alkaloid (corynantheine subclass)
Source	Secondary alkaloid in Mitragyna speciosa leaf
Typical leaf abundance	Approximately 8-9% of total alkaloid content (varies by strain and harvest)
Reported pharmacological activity	Smooth-muscle and spasmolytic activity in early research literature; lower MOR affinity than mitragynine in published assays
Relationship to mitragynine	Structurally related corynantheine-class alkaloid; shares core indole framework
Reference standard availability	Available from chemical-standards suppliers for analytical use

What is paynantheine?

Paynantheine is a secondary indole alkaloid in the leaves of Mitragyna speciosa. It belongs to the corynantheine subclass of indole alkaloids - the same structural family as mitragynine - and is typically the second most abundant alkaloid in kratom leaf, after mitragynine. Published HPLC quantification of leaf material places paynantheine at approximately 8-9% of total alkaloid content, though the exact value varies with strain, harvest, and processing.

Paynantheine has been identified and characterized in kratom research since the mid-20th century. Early phytochemistry literature describes smooth-muscle and spasmolytic activity in research models. More recent published in vitro receptor work generally reports weaker mu-opioid receptor binding affinity than mitragynine.

Paynantheine in kratom alkaloid pharmacology

Paynantheine has been studied as part of the broader characterization of the kratom alkaloid family. In published in vitro receptor assays, paynantheine shows lower binding affinity at the mu-opioid receptor than mitragynine and 7-hydroxymitragynine, and a different overall receptor profile. Whether and to what extent paynantheine contributes to the in vivo pharmacological profile of orally consumed kratom material is part of ongoing research. The compound's natural abundance is high enough that it warrants attention in any complete characterization of kratom leaf chemistry.

Quantification of paynantheine in commercial products is typically performed by HPLC with UV detection or by LC-MS/MS, alongside quantification of mitragynine and 7-OH. A Certificate of Analysis for a kratom product may report paynantheine as a percent-assay value, particularly for products marketed as standardized to a specific alkaloid profile.

Common questions about paynantheine

What is paynantheine?: A secondary indole alkaloid in Mitragyna speciosa (kratom) leaf, belonging to the corynantheine subclass. Typically the second most abundant alkaloid after mitragynine.
How abundant is paynantheine in kratom leaf?: Published HPLC quantification places paynantheine at approximately 8-9% of total alkaloid content, varying with strain, harvest, and processing.
What pharmacology has been reported for paynantheine?: Early phytochemistry literature reports smooth-muscle and spasmolytic activity in research models. More recent published in vitro receptor work reports weaker mu-opioid receptor binding affinity than mitragynine.
How does paynantheine relate structurally to mitragynine?: Both belong to the corynantheine subclass of indole alkaloids and share the core indole framework. They differ in specific substituents and stereochemistry.
Is paynantheine quantified on a Certificate of Analysis?: It can be. Many COAs for kratom and 7-OH products report paynantheine as a percent-assay value alongside mitragynine and 7-OH, particularly for products standardized to a specific alkaloid profile.

References

Brown PN, Lund JA, Murch SJ. (2017). A botanical, phytochemical and ethnomedicinal review of the genus Mitragyna korth. Journal of Ethnopharmacology.
Hassan Z, Muzaimi M, Navaratnam V, et al. (2013). From kratom to mitragynine and its derivatives. Neuroscience and Biobehavioral Reviews. PMID 23206666.
Sharma A, Kamble SH, León F, et al. (2019). Simultaneous quantification of ten key Kratom alkaloids in Mitragyna speciosa leaf extracts. Drug Testing and Analysis.
Beckett AH, Shellard EJ, Phillipson JD, et al. (1965). Alkaloids from Mitragyna speciosa (Korth.). Journal of Pharmacy and Pharmacology.

Important safety information:

Products containing 7-hydroxymitragynine (7-OH) are sold for adult use only (21+). These statements have not been evaluated by the U.S. Food and Drug Administration. Products are not intended to diagnose, treat, cure, or prevent any disease. The FDA has raised safety concerns regarding concentrated 7-OH products; consult a qualified healthcare professional before use. Do not operate vehicles or machinery after use. Keep out of reach of children and pets. Laws vary by state, buyers are responsible for knowing applicable law.