1490-04-6 Usage
Chemical Properties
Different sources of media describe the Chemical Properties of 1490-04-6 differently. You can refer to the following data:
1. colourless crystals
2. Racemic menthol is a mixture of equal parts of the (1R,2S,5R)- and
(1S,2R,5S)-isomers of menthol. It is a free-flowing or agglomerated
crystalline powder, or colorless, prismatic, or acicular shiny crystals,
or hexagonal or fused masses with a strong characteristic odor and
taste. The crystalline form may change with time owing to
sublimation within a closed vessel. The USP 32 specifies that
menthol may be either naturally occurring l-menthol or syntheti-cally prepared racemic or dl-menthol. However, the JP XV and
PhEur 6.0, along with other pharmacopeias, include two separate
monographs for racemic and l-menthol.
Uses
Different sources of media describe the Uses of 1490-04-6 differently. You can refer to the following data:
1. menthol is a fragrance. It is also said to be anti-septic, cooling, refreshing, and a blood-circulation stimulant. Menthol gives the skin a “cool” feeling after use. It constitutes almost 50 percent of peppermint oil but can also be synthetically produced through the hydrogenation of thymol. It is non-toxic in low doses, but in high concentrations it can be irritating to the skin, especially the mucous membranes.
2. Labelled Menthol. Used for oral gel patch or film containing herb extracts or Chinese medicine, fruit extract, spearmint, and menthol for smoking cessation.
3. Menthol is used in confectionery, perfumery, cough drops, cigarettes, liqueurs, etc.; topical antipruritic; local anesthetic; gastric sedative.
Definition
Different sources of media describe the Definition of 1490-04-6 differently. You can refer to the following data:
1. A white crystalline terpenealcohol, C10H19OH; r.d. 0.89;m.p. 42°C; b.p. 103–104°C. It has aminty taste and is found in certainessential oils (e.g. peppermint) andused as a flavouring.
2. ChEBI: Any secondary alcohol that is one of the eight possible diastereoisomers of 5-methyl-2-(propan-2-yl)cyclohexan-1-ol.
Production Methods
Menthol occurs widely in nature as l-menthol and is the principal
component of peppermint and cornmint oils obtained from the
Mentha piperita and Mentha arvensis species. Commercially, lmenthol
is mainly produced by extraction from these volatile oils. It
may also be prepared by partial or total synthetic methods.
Racemic menthol is prepared synthetically via a number of
routes, e.g. by hydrogenation of thymol.
Brand name
Fisherman’s Friend
Lozenges (Bristol-Myers Products); Therapeutic Mineral
Ice (Bristol-Myers Products).
Pharmaceutical Applications
Menthol is widely used in pharmaceuticals, confectionery, and
toiletry products as a flavoring agent or odor enhancer. In addition
to its characteristic peppermint flavor, l-menthol, which occurs
naturally, also exerts a cooling or refreshing sensation that is
exploited in many topical preparations. Unlike mannitol, which
exerts a similar effect due to a negative heat of solution, l-menthol
interacts directly with the body’s coldness receptors. d-Menthol has
no cooling effect, while racemic menthol exerts an effect approximately
half that of l-menthol.
When used to flavor tablets, menthol is generally dissolved in
ethanol (95%) and sprayed onto tablet granules and not used as a
solid excipient.
Menthol has been investigated as a skin-penetration enhancer
and is also used in perfumery, tobacco products, chewing gum and
as a therapeutic agent. When applied to the skin, menthol dilates the
blood vessels, causing a sensation of coldness followed by an
analgesic effect. It relieves itching and is used in creams, lotions, and
ointments. When administered orally in small doses menthol has a
carminative action.
Safety
Almost all toxicological data for menthol relate to its use as a
therapeutic agent rather than as an excipient. Inhalation or
ingestion of large quantities can result in serious adverse reactions
such as ataxia and CNS depression,hypersensitivity reactions,
severe abdominal pain, nausea, vomiting, vertigo, drowsiness, and
coma.Although menthol is essentially nonirritant there have been
some reports of hypersensitivity following topical application.
In a Polish study approximately 1% of individuals were determined
as being sensitive to menthol.There have been reports of apnea
and instant collapse in infants after the local application of menthol
to their nostrils.
The WHO has set an acceptable daily intake of menthol at up to
0.4 mg/kg body-weight.
LD50 (rat, IM): 10.0 g/kg
LD50 (rat, oral): 3.18 g/kg
storage
A formulation containing menthol 1% w/w in aqueous cream has
been reported to be stable for up to 18 months when stored at room
temperature.
Menthol should be stored in a well-closed container at a
temperature not exceeding 25°C, since it sublimes readily.
Incompatibilities
Incompatible with: butylchloral hydrate; camphor; chloral hydrate;
chromium trioxide; b-naphthol; phenol; potassium permanganate;
pyrogallol; resorcinol; and thymol.
Regulatory Status
Included in the FDA Inactive Ingredients Database (dental
preparations, inhalations, oral aerosols, capsules, solutions, suspensions,
syrups, and tablets; also topical preparations). Included in
nonparenteral medicines licensed in the UK. Accepted for use in
foods and confectionery as a flavoring agent of natural origin.
Included in the Canadian List of Acceptable Non-medicinal
Ingredients.
Check Digit Verification of cas no
The CAS Registry Mumber 1490-04-6 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 1,4,9 and 0 respectively; the second part has 2 digits, 0 and 4 respectively.
Calculate Digit Verification of CAS Registry Number 1490-04:
(6*1)+(5*4)+(4*9)+(3*0)+(2*0)+(1*4)=66
66 % 10 = 6
So 1490-04-6 is a valid CAS Registry Number.
InChI:InChI=1/2C10H20O/c2*1-7(2)9-5-4-8(3)6-10(9)11/h2*7-11H,4-6H2,1-3H3
1490-04-6Relevant articles and documents
Domino-cyclisation and hydrogenation of citronellal to menthol over bifunctional Ni/Zr-Beta and Zr-beta/Ni-MCM-41 catalysts
Nie, Yuntong,Chuah, Gaik-Khuan,Jaenicke, Stephan
, p. 790 - 792 (2006)
The one-pot conversion of (±)-citronellal to menthol can be selectively catalysed by either a bifunctional Ni/Zr-zeolite beta catalyst or a dual catalyst system of Zr-beta and Ni/MCM-41, giving a high diastereoselectivity to (±)-menthol of 90-94%. The Royal Society of Chemistry 2006.
STEREOSELECTIVE HYDROGENATION OF A MENTHONE-ISOMENTHONE MIXTURE ON HETEROGENEOUS NICKEL, NICKEL-COBALT, AND COBALT CATALYSTS
Zubareva, N. D.,Klabunovskii, E. I.,Kheifits, L. A.
, p. 1765 - 1768 (1989)
A study was carried out on the effect of the nature of the catalysts, additives, and solvents on the stereoselectivity of the liquid-phase hydrogenation of an equilibrium menthone-isomenthone mixture to give menthols.Neoisomenthol, which is the least stable of all the menthol isomers, was predominantly formed on a cobalt catalyst modified by (+)-tartaric acid in ethyl acetate at 130 deg C and 10 MPa.
Continuous synthesis of menthol from citronellal and citral over Ni-beta-zeolite-sepiolite composite catalyst
Er?nen, Kari,M?ki-Arvela, P?ivi,Martinez-Klimov, Mark,Muller, Joseph,Murzin, Dmitry Yu.,Peurla, Markus,Simakova, Irina,Vajglova, Zuzana
, (2022/04/03)
One-pot continuous synthesis of menthols both from citronellal and citral was investigated over 5 wt% Ni supported on H-Beta-38-sepiolite composite catalyst at 60–70 °C under 10–29 bar hydrogen pressure. A relatively high menthols yield of 53% and 49% and stereoselectivity to menthol of 71–76% and 72–74% were obtained from citronellal and citral respectively at the contact time 4.2 min, 70 °C and 20 bar. Citral conversion noticeably decreased with time-on-stream under 10 and 15 bar of hydrogen pressure accompanied by accumulation of citronellal, the primary hydrogenation product of citral, practically not affecting selectivity to menthol. A substantial amount of defuctionalization products observed during citral conversion, especially at the beginning of the reaction (ca. 1 h), indicated that all intermediates could contribute to formation of menthanes. Ni/H-Beta-38-sepiolite composite material prepared by extrusion was characterized by TEM, SEM, XPS, XRD, ICP-OES, N2 physisorption and FTIR techniques to perceive the interrelation between the physico-chemical and catalytic properties.
A synthetic process of L-menthol
-
Paragraph 0076; 0077; 0078, (2017/02/24)
The invention relates to the field of spice synthesis and particularly relates to a synthetic process of L-menthol. The process includes steps of d,l-menthol synthesizing, d,l-menthol rectification, d,l-menthol esterification, d,l-menthyl benzoate rectification, d,l-menthyl benzoate resolution, D-menthol synthesizing, menthol isomerization and L-menthol synthesizing. The process adopts thymol that is a simple, easily available and cheap chemical product as a raw material. Esterification conditions are optimized and the esterification and rectification are performed at the same time so as to allow the esterification to be converted into a way beneficial to d,l-menthyl benzoate production, thus increasing the esterification yield. Crystallization and resolution are optimized by utilization of the d,l-menthyl benzoate. Preparation of the L-menthol by the process is characterized by being high in yield, low in cost, simple and convenient in operation, suitable for continuous and large-scale production, and the like. According to the process, operation of the process is cyclic with a whole system being sealed, and the process is free of waste water, energy-saving and environmental friendly.
P450-catalyzed regio- and stereoselective oxidative hydroxylation of disubstituted cyclohexanes: Creation of three centers of chirality in a single CH-activation event This paper is dedicated to the memory of Harry H. Wasserman
Ilie, Adriana,Agudo, Rubén,Roiban, Gheorghe-Doru,Reetz, Manfred T.
, p. 470 - 475 (2015/02/02)
Wild-type P450-BM3 is able to catalyze in a highly regio- and diastereoselective manner the oxidative hydroxylation of non-activated disubstituted cyclohexane derivatives lacking any functional groups, including cis- and trans-1,2-dimethylcyclohexane, cis- and trans-1,4-dimethylcyclohexane, and trans-1,4-methylisopropylcyclohexane. In all cases except chiral trans-1,2-dimethylcyclohexane as substrate, the single hydroxylation event at a methylene group induces desymmetrization with simultaneous creation of three centers of chirality. Certain mutants increase selectivity, setting the stage for future directed evolution work.
