CA1098915A - Nitriles and method for their preparation - Google Patents
Nitriles and method for their preparationInfo
- Publication number
- CA1098915A CA1098915A CA258,267A CA258267A CA1098915A CA 1098915 A CA1098915 A CA 1098915A CA 258267 A CA258267 A CA 258267A CA 1098915 A CA1098915 A CA 1098915A
- Authority
- CA
- Canada
- Prior art keywords
- dimethyl
- hydroxy
- octenenitrile
- double bond
- preparation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C255/00—Carboxylic acid nitriles
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Fats And Perfumes (AREA)
- Cosmetics (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE.-Novel perfuming substances are disclosed, which are 3,7-dimethyl-3-hydroxy-octanenitrile, and 3,7-dimethyl-2-octenenitrile. A method for their preparation is also disclosed, which uses 3,7-dimethyl-3-hydroxy-6-octenenitrile as the start-ing material.
Description
as CA~E 890 This invention relates to novel terpene d.eriva-tives, and more parti.cularly to nitriles having the general formula .: ;
. l 2 3 4 5 6 7 8 CN - ~H - C - CH~ 2 CH2 CH - CH3 wherein the free valencies on the carbon atoms on the
. l 2 3 4 5 6 7 8 CN - ~H - C - CH~ 2 CH2 CH - CH3 wherein the free valencies on the carbon atoms on the
2 and 3 positi.ons are saturated by hydro~en and hydroxyl~
respectively 3 or are mutually saturated in order to originate a do~ble o:Lefin bond between the two carbon atoms referred to above: the invention is also related to the method for the preparation of such nitriles.
More particularly~ the present invention relates to / 3 ~ 3,7-dimethyl-3-hydroxy-octanenitrile ~I~
4 C~ 1 ¦ 1 CN
- 5 CH~
6 1~2 .
~3 8 CH3 fH3 - 3,7-dimethyl-2-octenenitrile ~II) j C ~ 2
respectively 3 or are mutually saturated in order to originate a do~ble o:Lefin bond between the two carbon atoms referred to above: the invention is also related to the method for the preparation of such nitriles.
More particularly~ the present invention relates to / 3 ~ 3,7-dimethyl-3-hydroxy-octanenitrile ~I~
4 C~ 1 ¦ 1 CN
- 5 CH~
6 1~2 .
~3 8 CH3 fH3 - 3,7-dimethyl-2-octenenitrile ~II) j C ~ 2
3 4 C~2 /\
G~3 8 ~3 2.
and to the method for their preparation.
The subject compounds - and more particularly the (II) - possess a characteristically pleasant scent which enables them to be used as perfumes and, still more particu-larly, f~r the formulation, in union with other known compounds, of perfumed mixtures which can be used for soaps, cosmetics, deodorants and the like. In this sense, they can replace with àdvantage, inter alia, the 3,7-dimethyl-2,6 octeneni-trile (III):
~ CN
which is best known as geranonitrile, in comparlson with which they have a sweetest note and an improved chemical stability.
In this connection, it should be noticed that, whereas the geranonitrile, by treatment for a few days at room temperature with a mixture of 98% H2SO~ and glacial CH3COOH
in the volume proportions of 5 to 25, yives rise, upon addition .of water, to poorly volatile pitchy substances, the compound (II), which is saturated at the 6 and ? positions, remains unaltered.
Another important application of the compounds which form the subject-matter of this invention is their use as intermediates in a number of organic syntheses.
Their preparation takes place as follows:
a) hydrogenating the double bond at 6,7 of 3,7- dimethyl-3-hydroxy-6-octenenitrile (IV) :
~OH
~ (IV) ' \ CN
~
to obtain 3,7-dimethyl-3-hydroxy-octanenitrile, or . _ b) hydrogenating the double bond at 6,7 of 3,7-dime-thyl-3-hydroxy-6-octenenitrile and then dehydrating the same at 2,3 to provide the necessary double bond for the desired 3,7-dimethyl-2-octenenitrile.
The starting material of formula (I~) can be obtained, in its turn, according to an original synthesis as disclosed in Canadian patent No..1,047,535 .issued on January 30, 1979 in the name of -the same Applicant~ as can be seen in the following illustrative and non-limitative examples :
- 3a -~L ~
EXAMPLE
5.28 ~rams of 3,7-dimethyl-3-hydroxy-6-octene-nitrile (IV ) in 25 mls hexane~ supplemented by 0~52 grams of palladium on acti~ated char (5% Pd by wei~ht ), are hydrogenated.with stirring3 in a glass apparatus, ~t room temperature, and under a hydrogel1 pressure of 760 + i.OO millimeters of mercury5 abs. p1essure.
The absorption o-f the stoichiometrical amount of hydrogen relati~e to the saturation of the double bond of IV takes about one hour.
On completion of this stage, the catalyst is filtered off and the solvent is e~aporated under vacu.um, and 3,7-dimethyl-3~h~droxy octanenitril.e (I ) is collect-ed, the conversion rate and the selectivity being both 15 over 90%.
By subsequent distillation in a vacuo with a Vigreux col.~nn, a product is o~tained which has a purity of about 98% and a boili.ng point temperature of 83C-840C under an abs. pressure of 0.3 ~nHg.
The compound I i.5 obtai.ned with the same rati.o between the reactants of Example l~ but by carrying out the hydrogenation i.n a steel autoclave under an ini-tial pressure of hydrvgen of 8.6 kilograms per square centi-meter (gauge).
The procedure or collectir1g and puri.fyin~ the product are Yery much the same as set out in Example l.
2 grams of 3~7-dimethyl-3-hydroxy-octanenitrile (~) 3 and 3 grams o basic Woelm a3.uminum oxide are kept during one hour and a halE at 220C ~ 230C under a nitrogen s-tream in a glass -F1.ask. equipped with a bubble condenser ~hich is coolcd wi~h water.
On completion of this sta~e~ the mi.xture is allow-L~f', . :
ed to eool at room temperature~ ~ ~ the reacti.on mass is taken up with ethyl ether and filtered, the sol~ent being then thoroughly evaporated off.
Thus~ 3,7-climethyl-2~octenenitrile (II ) i.s obtain-ed~ whieh is composed by a mixture of the cis- and trans-isomers in a ratio of 45/55 approximately7 tlle selecti-vity being not less -than 90%.
The product (II) can be obtained at a purity of 98% appro~. by subjecting the residue as described here-inabove to distillation in a ~aeuo and collecting the product ~hich boils at 52C-53~C under an abs. pressure o 0.1 mmHg.
The charactcri~ation of the compound.s in quefiti.on has been effected by IR, N:MR and mass-spectrography analyses.
The IR spec-trum confirms the presenee of tne following functional groups :
- OH
- C N (non conj.~ 2252 em ~for the compGund. (I) ~ C-O of a tert.alcohol 1153 cm = C-ll 3045 em - C - N (con~.at alpha)2215 em )for the compouncl (I:C) C = C (conj. ) 1630 cm = C-H (stretehing~ 700 cm )~
The N~ analysis (solvent CC14~ i.nterll~.1. stand rd H~)S) has indicated t~le follo~ing charac-teristic si~nals - Oll 3.23 parts per mil ion (ppm) 2 ( 2.42 ppm 3 - CH2-14) 3 Cll ~ 1-45 ppm ) - CH3 ( 1 24 ppm ) for the compound (I3 - C1l2- ~5~ ) ~ CH3 ~ ) C \ Q.83 ppm ) .~
= CfI 5.03 ppm - CH2- (4) 2.08 ppm - CH3 ~sis~or trans~ 8 ppm - CJ3 (trans-or cis-) l,85 ppm ( for the compoun~
~ C~2 ~ (6 ) l.SO ~pm -- C112 - (5 ) CH 1.20 ppm / C~13 C 0.8l ppm Mass spectrometry confirms the molecular ~eights (l69 for I and 15l fols:LI) and the respective e~pected.
structures.
G~3 8 ~3 2.
and to the method for their preparation.
The subject compounds - and more particularly the (II) - possess a characteristically pleasant scent which enables them to be used as perfumes and, still more particu-larly, f~r the formulation, in union with other known compounds, of perfumed mixtures which can be used for soaps, cosmetics, deodorants and the like. In this sense, they can replace with àdvantage, inter alia, the 3,7-dimethyl-2,6 octeneni-trile (III):
~ CN
which is best known as geranonitrile, in comparlson with which they have a sweetest note and an improved chemical stability.
In this connection, it should be noticed that, whereas the geranonitrile, by treatment for a few days at room temperature with a mixture of 98% H2SO~ and glacial CH3COOH
in the volume proportions of 5 to 25, yives rise, upon addition .of water, to poorly volatile pitchy substances, the compound (II), which is saturated at the 6 and ? positions, remains unaltered.
Another important application of the compounds which form the subject-matter of this invention is their use as intermediates in a number of organic syntheses.
Their preparation takes place as follows:
a) hydrogenating the double bond at 6,7 of 3,7- dimethyl-3-hydroxy-6-octenenitrile (IV) :
~OH
~ (IV) ' \ CN
~
to obtain 3,7-dimethyl-3-hydroxy-octanenitrile, or . _ b) hydrogenating the double bond at 6,7 of 3,7-dime-thyl-3-hydroxy-6-octenenitrile and then dehydrating the same at 2,3 to provide the necessary double bond for the desired 3,7-dimethyl-2-octenenitrile.
The starting material of formula (I~) can be obtained, in its turn, according to an original synthesis as disclosed in Canadian patent No..1,047,535 .issued on January 30, 1979 in the name of -the same Applicant~ as can be seen in the following illustrative and non-limitative examples :
- 3a -~L ~
EXAMPLE
5.28 ~rams of 3,7-dimethyl-3-hydroxy-6-octene-nitrile (IV ) in 25 mls hexane~ supplemented by 0~52 grams of palladium on acti~ated char (5% Pd by wei~ht ), are hydrogenated.with stirring3 in a glass apparatus, ~t room temperature, and under a hydrogel1 pressure of 760 + i.OO millimeters of mercury5 abs. p1essure.
The absorption o-f the stoichiometrical amount of hydrogen relati~e to the saturation of the double bond of IV takes about one hour.
On completion of this stage, the catalyst is filtered off and the solvent is e~aporated under vacu.um, and 3,7-dimethyl-3~h~droxy octanenitril.e (I ) is collect-ed, the conversion rate and the selectivity being both 15 over 90%.
By subsequent distillation in a vacuo with a Vigreux col.~nn, a product is o~tained which has a purity of about 98% and a boili.ng point temperature of 83C-840C under an abs. pressure of 0.3 ~nHg.
The compound I i.5 obtai.ned with the same rati.o between the reactants of Example l~ but by carrying out the hydrogenation i.n a steel autoclave under an ini-tial pressure of hydrvgen of 8.6 kilograms per square centi-meter (gauge).
The procedure or collectir1g and puri.fyin~ the product are Yery much the same as set out in Example l.
2 grams of 3~7-dimethyl-3-hydroxy-octanenitrile (~) 3 and 3 grams o basic Woelm a3.uminum oxide are kept during one hour and a halE at 220C ~ 230C under a nitrogen s-tream in a glass -F1.ask. equipped with a bubble condenser ~hich is coolcd wi~h water.
On completion of this sta~e~ the mi.xture is allow-L~f', . :
ed to eool at room temperature~ ~ ~ the reacti.on mass is taken up with ethyl ether and filtered, the sol~ent being then thoroughly evaporated off.
Thus~ 3,7-climethyl-2~octenenitrile (II ) i.s obtain-ed~ whieh is composed by a mixture of the cis- and trans-isomers in a ratio of 45/55 approximately7 tlle selecti-vity being not less -than 90%.
The product (II) can be obtained at a purity of 98% appro~. by subjecting the residue as described here-inabove to distillation in a ~aeuo and collecting the product ~hich boils at 52C-53~C under an abs. pressure o 0.1 mmHg.
The charactcri~ation of the compound.s in quefiti.on has been effected by IR, N:MR and mass-spectrography analyses.
The IR spec-trum confirms the presenee of tne following functional groups :
- OH
- C N (non conj.~ 2252 em ~for the compGund. (I) ~ C-O of a tert.alcohol 1153 cm = C-ll 3045 em - C - N (con~.at alpha)2215 em )for the compouncl (I:C) C = C (conj. ) 1630 cm = C-H (stretehing~ 700 cm )~
The N~ analysis (solvent CC14~ i.nterll~.1. stand rd H~)S) has indicated t~le follo~ing charac-teristic si~nals - Oll 3.23 parts per mil ion (ppm) 2 ( 2.42 ppm 3 - CH2-14) 3 Cll ~ 1-45 ppm ) - CH3 ( 1 24 ppm ) for the compound (I3 - C1l2- ~5~ ) ~ CH3 ~ ) C \ Q.83 ppm ) .~
= CfI 5.03 ppm - CH2- (4) 2.08 ppm - CH3 ~sis~or trans~ 8 ppm - CJ3 (trans-or cis-) l,85 ppm ( for the compoun~
~ C~2 ~ (6 ) l.SO ~pm -- C112 - (5 ) CH 1.20 ppm / C~13 C 0.8l ppm Mass spectrometry confirms the molecular ~eights (l69 for I and 15l fols:LI) and the respective e~pected.
structures.
Claims (6)
1. Method for the preparation of nitriles having the general formula:
wherein the free valencies on the carbon atoms in the 2 and 3 positions are saturated by hydrogen and hydroxyl, respectively, or are mutually saturated to originate a double olefin bond between the two carbon atoms referred to above, said process which comprises:
a) hydrogenating the double bond at 6,7 of 3,7-dime-thyl-3-hydroxy-6-octenenitrile to obtain 3,7-dimethyl-3-hydroxy-octanenitrile, or b) hydrogenating the double bond at 6,7 of 3,7-dime-thyl-3-hydroxy-6-octenenitrile and then dehydrating the same at 2,3 to provide the necessary double bond for the desired 3,7-dimethyl-2-octenenitrile.
wherein the free valencies on the carbon atoms in the 2 and 3 positions are saturated by hydrogen and hydroxyl, respectively, or are mutually saturated to originate a double olefin bond between the two carbon atoms referred to above, said process which comprises:
a) hydrogenating the double bond at 6,7 of 3,7-dime-thyl-3-hydroxy-6-octenenitrile to obtain 3,7-dimethyl-3-hydroxy-octanenitrile, or b) hydrogenating the double bond at 6,7 of 3,7-dime-thyl-3-hydroxy-6-octenenitrile and then dehydrating the same at 2,3 to provide the necessary double bond for the desired 3,7-dimethyl-2-octenenitrile.
2. Metnod for the preparation of 3,7-dimethyl-3-hydroxy-octanenitrile which comprises hydrogenating the double bond at 6,7 of 3,7-dimethyl-3-hydroxy-6-octenenitrile.
3. Method for the preparation of 3,7-dimethyl-2-octenenitrile which comprises hydrogenating the double bond at 6,7 of 3,7-dimethyl-3-hydroxy-6-octenenitrile and then dehydrating the same at 2,3 to provide the necessary double bond for the desired nitrile.
4. Nitriles having the general formula:
wherein the free valencies on the carbon atoms in the 2 and 3 positions are saturated by hydrogen and hydroxyl, respec-tively, or are mutually saturated to originate a double olefin bond between the two carbon atoms referred to above.
wherein the free valencies on the carbon atoms in the 2 and 3 positions are saturated by hydrogen and hydroxyl, respec-tively, or are mutually saturated to originate a double olefin bond between the two carbon atoms referred to above.
5. 3,7-dimethyl-3-hydroxy-octanenitrile.
6. 3,7-dimethyl-2-octenenitrile.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT26221A/75 | 1975-08-08 | ||
| IT26221/75A IT1040373B (en) | 1975-08-08 | 1975-08-08 | NITRILS AND PROCEDURE FOR THE LORD PREPARATION |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1098915A true CA1098915A (en) | 1981-04-07 |
Family
ID=11218973
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA258,267A Expired CA1098915A (en) | 1975-08-08 | 1976-08-02 | Nitriles and method for their preparation |
Country Status (31)
| Country | Link |
|---|---|
| JP (1) | JPS5219623A (en) |
| AT (1) | AT345780B (en) |
| AU (1) | AU499775B2 (en) |
| BE (1) | BE844977A (en) |
| BG (1) | BG24667A3 (en) |
| BR (1) | BR7605212A (en) |
| CA (1) | CA1098915A (en) |
| CH (1) | CH628024A5 (en) |
| CS (2) | CS191998B2 (en) |
| DD (1) | DD125743A5 (en) |
| DE (1) | DE2635545C3 (en) |
| DK (1) | DK355576A (en) |
| ES (1) | ES450918A1 (en) |
| FR (1) | FR2320289A1 (en) |
| GB (1) | GB1523028A (en) |
| HU (2) | HU174410B (en) |
| IE (1) | IE43510B1 (en) |
| IN (1) | IN144716B (en) |
| IT (1) | IT1040373B (en) |
| LU (1) | LU75553A1 (en) |
| MX (1) | MX3857E (en) |
| NL (1) | NL169998C (en) |
| NO (1) | NO142959C (en) |
| PL (1) | PL101728B1 (en) |
| PT (1) | PT65448B (en) |
| RO (1) | RO69916A (en) |
| SE (1) | SE7608868L (en) |
| SU (1) | SU617009A3 (en) |
| TR (1) | TR19097A (en) |
| YU (1) | YU192276A (en) |
| ZA (1) | ZA764471B (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5495821A (en) * | 1977-12-27 | 1979-07-28 | Cummins Engine Co Inc | Method of recirculating part of exhaust gas for reducing pullutant |
| US4277377A (en) * | 1979-03-22 | 1981-07-07 | Bush Boake Allen Limited | Perfume compositions containing dimethyl heptenonitriles |
| US4863631A (en) * | 1988-06-24 | 1989-09-05 | International Flavors & Fragrances Inc. | Dimethyl substituted alkyl nitriles, perfume and bleach compositions containing same organoleptic uses thereof and process intermediates for producing same |
| DE3914391A1 (en) * | 1989-04-29 | 1991-01-17 | Basf Ag | SS, (GAMMA) - UNSATURATED NITRILES, THEIR PRODUCTION AND USE AS A FRAGRANCE |
| DE10247966A1 (en) | 2002-10-15 | 2004-05-06 | Symrise Gmbh & Co. Kg | 5,7,7-trimethyloctanenitrile |
| MX2011002550A (en) * | 2008-10-13 | 2011-04-04 | Firmenich & Cie | Chemically stable ingredients as lemon odorant. |
| EP3612620B1 (en) * | 2017-04-21 | 2021-03-03 | Symrise AG | 4-ethyl-octene-2/3-nitrile as a fragrance |
-
1975
- 1975-08-08 IT IT26221/75A patent/IT1040373B/en active
-
1976
- 1976-07-26 ZA ZA764471A patent/ZA764471B/en unknown
- 1976-07-27 IN IN1337/CAL/76A patent/IN144716B/en unknown
- 1976-07-29 AU AU16379/76A patent/AU499775B2/en not_active Expired
- 1976-07-30 TR TR19097A patent/TR19097A/en unknown
- 1976-08-02 RO RO7687182A patent/RO69916A/en unknown
- 1976-08-02 CA CA258,267A patent/CA1098915A/en not_active Expired
- 1976-08-04 BG BG033922A patent/BG24667A3/en unknown
- 1976-08-04 YU YU01922/76A patent/YU192276A/en unknown
- 1976-08-04 CH CH997476A patent/CH628024A5/en not_active IP Right Cessation
- 1976-08-05 NO NO762718A patent/NO142959C/en unknown
- 1976-08-05 FR FR7623966A patent/FR2320289A1/en active Granted
- 1976-08-05 GB GB32731/76A patent/GB1523028A/en not_active Expired
- 1976-08-05 IE IE1737/76A patent/IE43510B1/en unknown
- 1976-08-05 PL PL1976191642A patent/PL101728B1/en unknown
- 1976-08-06 ES ES450918A patent/ES450918A1/en not_active Expired
- 1976-08-06 LU LU75553A patent/LU75553A1/xx unknown
- 1976-08-06 SU SU762388805A patent/SU617009A3/en active
- 1976-08-06 DD DD194231A patent/DD125743A5/xx unknown
- 1976-08-06 MX MX762138U patent/MX3857E/en unknown
- 1976-08-06 PT PT65448A patent/PT65448B/en unknown
- 1976-08-06 CS CS771757A patent/CS191998B2/en unknown
- 1976-08-06 BR BR7605212A patent/BR7605212A/en unknown
- 1976-08-06 BE BE169635A patent/BE844977A/en not_active IP Right Cessation
- 1976-08-06 AT AT585476A patent/AT345780B/en active
- 1976-08-06 SE SE7608868A patent/SE7608868L/en unknown
- 1976-08-06 DE DE2635545A patent/DE2635545C3/en not_active Expired
- 1976-08-06 HU HU76AI261A patent/HU174410B/en unknown
- 1976-08-06 CS CS765150A patent/CS191982B2/en unknown
- 1976-08-06 DK DK355576A patent/DK355576A/en not_active Application Discontinuation
- 1976-08-06 HU HU76AI283A patent/HU177537B/en unknown
- 1976-08-06 JP JP51093265A patent/JPS5219623A/en active Pending
- 1976-08-09 NL NLAANVRAGE7608847,A patent/NL169998C/en not_active IP Right Cessation
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