162 to 164 °C (324 to 327 °F; 435 to 437 K) (R-(−)-enantiomer); 184 to 185 °C (racemate)
Solubility in water
soluble
Pharmacology
ATC code
C01CA08 (WHO) S01GA06 (WHO), QS01FB90 (WHO)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references
Chemical compound
Synephrine, or, more specifically, p-synephrine, is an alkaloid, occurring naturally in some plants and animals, and also in approved drugs products as its m-substituted analog known as neo-synephrine.[1]p-Synephrine (or formerly Sympatol and oxedrine [BAN]) and m-synephrine are known for their longer acting adrenergic effects compared to epinephrine and norepinephrine. This substance is present at very low concentrations in common foodstuffs such as orange juice and other orange (Citrus species) products, both of the "sweet" and "bitter" variety. The preparations used in traditional Chinese medicine (TCM), also known as Zhi Shi (枳实), are the immature and dried whole oranges from Citrus aurantium (Fructus Aurantii Immaturus). Extracts of the same material or purified synephrine are also marketed in the US, sometimes in combination with caffeine, as a weight-loss-promoting dietary supplement for oral consumption. While the traditional preparations have been in use for millennia as a component of TCM-formulas, synephrine itself is not an approved over the counter drug. As a pharmaceutical, m-synephrine (phenylephrine) is still used as a sympathomimetic (i.e. for its hypertensive and vasoconstrictor properties), mostly by injection for the treatment of emergencies such as shock, and rarely orally for the treatment of bronchial problems associated with asthma and hay-fever.[a]
There is a difference between studies concerning synephrine as a single chemical entity (synephrine can exist in the form of either of two stereoisomers, d- and l-synephrine, which are chemically and pharmacologically distinct), and synephrine which is mixed with other drugs and/or botanical extracts in a "supplement", as well as synephrine which is present as only one chemical component in a naturally-occurring mixture of phytochemicals such as the rind or fruit of a bitter orange. Mixtures containing synephrine as only one of their chemical components (regardless of whether these are of synthetic or natural origin) should not be assumed to produce exactly the same biological effects as synephrine alone.[2]
In physical appearance, synephrine is a colorless, crystalline solid and is water-soluble. Its molecular structure is based on a phenethylamine skeleton and is related to those of many other drugs and to the major neurotransmitters epinephrine and norepinephrine.
^SA, HCI Solutions. "Neo-Synephrine HCl - compendium.ch". compendium.ch. Archived from the original on 2020-07-25. Retrieved 2016-03-06.
^Wagner H., Ulrich-Merzenich G. (2009). "Synergy research: approaching a new generation of phytopharmaceuticals". Phytomedicine. 16 (2–3): 97–110. doi:10.1016/j.phymed.2008.12.018. PMID 19211237. S2CID 25766699.
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Synephrine, or, more specifically, p-synephrine, is an alkaloid, occurring naturally in some plants and animals, and also in approved drugs products as...
as a stimulant and appetite suppressant, due to its active ingredient, synephrine. Bitter orange supplements have been linked to a number of serious side...
for intravenous use" (PDF). U.S. Food and Drug Administration. "Neo-Synephrine Nasal Spray Drug Information, Professional". drugs.com. Archived from...
inhibitors), Citrus aurantium (contains small amounts of the stimulant synephrine), glaucine (plant derived compound usually used as cough medicine), and...
Isoprenaline Isopropylamphetamine Methylhexanamine Octopamine Phenpromethamine Synephrine Pre-workout Anderson WG (June 1983). "The sympathomimetic activity of...
and 2,5-DMA. It is no longer marketed.[why?] Sertraline Phenylephrine Synephrine Phentolamine Midodrine Pazdernik TL, Kerecsen L (2007) [2003]. "5". In...
nutrients, most health-benefitting compounds present in the fruit's peel are: Synephrine, a compound known to enhance lipid metabolism and increase metabolic rate...
This includes oxymetazoline (e.g., Afrin), phenylephrine (e.g., Neo-Synephrine), naphazoline (e.g., Privine), and l-desoxyephedrine/levomethamphetamine...
neurotransmitters and neuromodulators (including tyramine, octopamine, and synephrine) in the hypothalamus, amygdala, and dopaminergic system. People with migraine...
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