Talk:Terpene

message: I've made some extensive changes to this article, trying to expand it from the bare bones state that it was in.  If anyone has any suggestions for improvement or additional information needed, please let me know and I'll try to add it or feel free to just make the changes.  I would like to redo some of the images so that they are presented in a consistent style (I used some images from different articles, using them as place-holders for now.)   The article is still sparse in the later sections, but at least the current article provides a framework for filling in, I think.   Edgar181 05:01, 17 December 2005 (UTC)
thread_title: Edits

message: The 'terp' root of the word... where does that come from?  Turtles?  I suppose the rings can look sort of turtle-like... but seriously, this is something that I have not been able to find out, even after consulting the multivolume Oxford English Dicionary at school.
:I don't know for sure, but my guess is that the word terpene is derived from turpentine, which in turn is probably derived from the plant source it was originally produced from.  --Ed (Edgar181)
::Wouldn't turpentine be a derivative from Terpene, as turpentine is made of terpenes?Atebo88 (talk) 05:23, 30 November 2009 (UTC)
replies: text: It's explained under turpentine. 84.227.252.224 (talk) 20:26, 14 October 2014 (UTC)
thread_title:  Etymology 

message: Any discussion about terpenes and their role in possibly alleopathic plants like salvia leucophylla or eucalyptus?
=== Toxicity?===
leathal doses..etc..  —Preceding unsigned comment added by 71.42.147.99 (talk) 08:08, 18 September 2007 (UTC)
thread_title:  Alleopathy? 

message: leathal doses..etc..  —Preceding unsigned comment added by 71.42.147.99 (talk) 08:08, 18 September 2007 (UTC)
thread_title:  Toxicity?

message: A brief statement about the differences between terpene and terpendoid would be helpful to me. 67.232.173.26 (talk) 12:15, 26 April 2011 (UTC)
thread_title:  Terpene versus terpenoid (isoprenoid) 

message: I was reading about beer and noticed that the hops page under "brewing"  and the terpene page list different chemicals as the "four major components of hop essential oils".  One shows pinene, the other farnesene.  I'm not sure if there's a contradiction there, but it should be looked at by someone who knows.  Ramireja (talk) 13:52, 6 January 2012 (UTC)
thread_title:  Hop Compunds? 

message: Many of the examples given are terpenoids rather than terpenes (and therefore do not have the molecular formulas given).
I doubt all diterpenes have antimicrobial and antiinflammatory activity; this should probably read "Some are known to be antimicrobial and antiinflammatory."
In norisoprenoids peroxydases should be peroxidases. Glycosidases would not produce norisoprenoids.
69.72.92.118 (talk) 05:42, 10 September 2014 (UTC)
replies: text: Thanks for your suggestions for correcting and improving this article.  The terms "terpene" and "terpenoid" are often used interchangeably.  As this article says, "Some authors will use the term terpene to include all terpenoids".  So in that context I don't see an issue with how the article may conflate the two, but for clarity it is probably better to include the names of the terpenoid subtypes so I have done so.  I agree with you about the statement regarding antimicrobial and antiinflammatory activity and have simply removed it.  I corrected the misspelling of peroxidases.  Finally, the reference given for the statement about glycosidases producing norisoprenoids seems to support the statement.  The abstract says that glycosidase activities increase the levels of C13-norisoprenoids (I don't have access to the full article, only the abstract, so I'm not sure if this is a direct or indirect effect).  -- Ed (Edgar181) 12:42, 10 September 2014 (UTC)
thread_title:  Types 

message: "Terpenes are derived biosynthetically from units of isoprene"
I don't think this phrase is entirely accurate because terpenes are not actually built up from isoprene units. This is clarified in the next paragraph where the article talks about biosynthesis from IPP and DMAPP.
I think it should be clarified that the isoprene rule for predicting the structure and that it is not descriptive of the biosynthetic pathway. 
For example, it could say: "Terpenes can be viewed as oligomers of five carbon isoprene units, with the formula C5H8"
Beanstash (talk) 18:22, 18 September 2014 (UTC)
thread_title:  Biosynthesis 

message: (1) Were aromatic compounds really named for their strong aromas? The aromaticity article says both a qualified, careful no (at the top) and yes (in the body). The terpene article says yes. 
(2) Is it really true that terpenes are often (chemically speaking) aromatic? The aromaticity article says no (at the top), the terpene article says yes (at the top).
(3) Do strong-smelling substances and/or terpenes really have a protective function due to their ability to drive off parasites? The terpene article says yes, but in view of the other doubtful statements about strong aromas, I'd like to see some evidence. 84.227.252.224 (talk) 20:38, 14 October 2014 (UTC)
thread_title:  Aromatic statements doubtful 

message: This artyicle says how terpenes are biosynthaszed, but I did not see an explication of what they are. At a minimum I recommend including the statement from the page Category:Terpenes and terpenoids, "A terpene is a naturally occurring hydrocarbon based on combinations of the isoprene unit." I also recommend including a link to this very helpful page, should there be a way to do that :Category:Terpenes and terpenoids.
I don't know why this article has so much to say about terpenoids when there is a separate article about them, but if the terpenoid material must stay, I suggest also including the other statement, "Terpenoids are compounds related to terpenes, which may include some oxygen functionality or some rearrangement, however, the two terms are often used interchangeably." Page Notes (talk) 13:10, 15 April 2019 (UTC)
thread_title:  What is a terpene 

message: Terpenes are a vast and interesting class of compounds. I could write a book on this topic and never need to go into this kind of detail. I think this section is abstracted from someone’s PhD dissertation. It dominates the article with intellectual obtuseness. Really. I’m very much more chemically literate than the average American college science graduate, and this section is non-accessible. It has to go. It could be replaced for the average high school or community college American with a one accessible vernacular paragraph about plant synthesis. To write such a paragraph is a substantially greater challenge than the abstract here. Sbalfour (talk) 21:46, 3 November 2020 (UTC)
thread_title:  Biosynthesis 

message: A large block of info on the general properties of these compounds is missing: i.e. in addition to being smelly and oily generally, they’re highly non-polar liquids at room temperature, so extraction requires petroleum solvents. And they’re often volatile, flammable, toxic, the lighter molecular weight ones may be absorbed thru the skin, and they’re solvents themselves, so how they’re stored and collected needs to be carefully considered. As a practical matter, working with these chemicals requires expertise because they’re not very pleasant, though most of the time we don’t find these outside a chemical laboratory or industrial complex. Turpentine is exemplary of them. Sbalfour (talk) 11:13, 5 November 2020 (UTC)
thread_title:  Physical and chemical properties 

message: Given there are many thousands of named terpenes and terpenoids and probably millions with substantive industrial and commercial applications, do we really want to emphasize recreational cannabinoids? They’re still strictly illegal in most places. I think this whole rather lengthy paragraph would be better placed in the Cannabis sativa article. It’s a subtle brand of ‘aggrandizing erudition’. Sbalfour (talk) 12:18, 5 November 2020 (UTC)
replies: text: I am uncertain what the deal is.  One issue is that canabinoids are terpenoids not terpenes, and this article is about the latter.  But casual readers wont know that distinction and will be disappointed.  In any case, I inserted a picture of tetrahydrocannabinol.--Smokefoot (talk) 13:31, 11 March 2024 (UTC)
thread_title:  Cannabinoids 

message: This section seems superfluous, a whole level 2 section for two sentences? Other organic chemical articles don’t have terminology sections. This is interesting footnote type info. There’s already an elaboration of the term “terpenoid” in the lead, so we don’t need it here. Sbalfour (talk) 22:49, 5 November 2020 (UTC)
thread_title:  Terminology 

message: We’ve mentioned beta carotene and α-pinene in the article without any elaboration of what these signify. The isomeric structure of terpenes is evident and prominent, and in various areas like diet and pharmacology, the differences cannot be ignored. I propose some discussion of this on the Structure section. Sbalfour (talk) 14:36, 6 November 2020 (UTC)
thread_title:  Isomers 

message: This section is more aptly named "Taxonomy".  There's little or nothing here about the structure of terpenes, which would include exposition of isomers, cyclic and chain structures, chirality, homology and possibly crystallography. So I think the section should be split off and renamed, and a separate section Structure added. Sbalfour (talk) 19:54, 11 November 2020 (UTC)
thread_title:  Structure and types 

message: According to Ullmann's "the industrially most important terpenes":
*Myrcene: precursor to resins
*p-Menthane: precursor to "1-isopropyl-4-methylcyclohexane hydroperoxide" (rad inititor)
*α-Terpinene, 1,8-Cineole, 3-Carene, pinane, terpinolene: precursors to perfumes or odorants
*p-Cymene: solvent and perfume precursor, economically noncompetitive precursor to terephthalic acid 
*2-Pinane hydroperoxide for polymerization of dienes
*2-Pinanol: precursor to linalool
*Camphene: odorant; intermediate to camphor, isobornyl esters, and Toxaphen
--Smokefoot (talk) 23:36, 13 November 2020 (UTC)
thread_title: Uses from Ullmann

message: The second sentence of the Biosynthesis section reads "The isoprene units are provided from isoprenyl pyrophosphate and dimethylallyl pyrophosphate, which exist in equilibrium." But according to the article to which both those links lead, they are two names for the same substance. Maproom (talk) 22:20, 26 November 2020 (UTC)
replies: text: Well that's a problem.  Probably my fault.  A quick check suggests that the two species in equilibrium are isoprenyl pyrophosphate and isopentenyl pyrophosphate.  BTW, you are invited to look over what we have so far.  I redrafted a lot of the first half but another highly experienced editor thinks that the lede especially is too technical and missing info that would be relevant to an nonexpert.--Smokefoot (talk) 23:49, 26 November 2020 (UTC)
thread_title:  Confusing statement 

message: Not totally surprisingly, some deletions have occurred on the cannabis paragraph in the Terpene article.
1. I consider it important that cannabis be referenced in this article; cannabis is one of the most frequent topics invoked by "terpenes" (do a Google search). Someone who looks up "terpene" for that common reason needs to have some factual information provided.
2. Ferber et al. (2020) is a review article, with 107 primary sources.
3. The 2017 Russo & Marcu review article contains a summary (200 primary sources) of experimentation related to the "entourage" effect. The quote added by  72.249.250.57 is in the abstract of the article, but a (careful) read of the (technical) article shows that that quoted sentence is necessarily based on in-vitro and animal studies, as there are virtually *no* clinical experiments on humans (which is what the original sentence referred to). E.g., Russo's "Conclusion" states "Clinical trials that examine synergistic effects of cannabinoid components are sorely needed". So, currently, it is not known whether the hypothesis is true or false in humans.
4. The widely hypothesized effect of terpenes on cannabinoids is definitely an "application" in the cannabis growth and edibles industry.  Again, do a Google search. Finney1234 (talk) 21:15, 5 October 2021 (UTC)
thread_title:  Cannabis and Terpenes (2)