COURSE : CHEMISTRY OF NATURAL MATERIALS
CREDITS : 2
LECTURER : Dr. Syamsurizal, M.Si
TIME : 22-29 December 2012
1. Explain
the triterpenoid biosynthetic pathway, identify important factors that
determine the quantities produced many triterpenoids.
The
mechanism of the reaction steps of terpenoid biosynthesis is activated
by acetic acid as coenzyme A did produce acid Claisen type condensation
asetoasetat. Results
compounds with acetyl coenzyme A did aldol type condensation produces
branched carbon chains as found in mevalinat acid, subsequent reactions
are fosforialsi, elimination of phosphoric acid and decarboxylation
produces isopentenyl (IPP) who later became dimethyl allyl
berisomerisasi piropospat (DMAPP) by enzimisomeriasi. IPP
as isoprene unti actively joined the head to ekordengan DMAPP and this
merger is the first step of the polymerization of isoprene to produce
terpenoids. The
merger occurred due to electron attack of the double bond carbon atoms
of IPP to DMAPP electron deficient followed by the removal of ions that
produce geranil.pirofosfat pyrophosphate (GPP) is an intermediate for
all monoterpenoid compounds. The
merger between the IPP and GPP unti the same mechanism produces
Farnesil pyrophosphate (FPP), which is an intermediate for all compounds
seskuiterpenoid. Diterpenoid
compounds derived from geranil-geranil Pyrophosphate (GGPP) derived
from the condensation between one unit of IPP and GPP by the same
mechanism.
Biosynthesis of terpenoids occurred three basic reactions are:1.Pembentukan active isoprene derived from acetic acid via mevalonic acid.2.Penggabungan head and tail of two isoprene units to form mono-, seskui-, di-. Sester-, and poly-terpenoids.3.Penggabungan tail and tail of unit C-15 or C-20 produces triterpenoids and steroids.
In the biosynthesis of important factors to consider conditions on the yield triterpenoid biosynthetic process that occurs with respect to the enzymes involved in the reaction in the form of the enzyme HMG-CoA synthase, the enzyme HMG-CoA reductase, the enzyme and enzyme fosfomevalonat mevalonic kinase kinase, pirofosfomevalonat decarboxylase enzyme which in IPP isomerase enzyme because the enzyme can form isopentenyl pyrophosphate (IPP), which later became berisomerisasi Dimethyl allyl pyrophosphate (DMAPP). enzymes useful to accelerate the rate of reaction, and finish with a maximum biosynthesis. The presence of the enzyme can speed up reactions that require little energy.
2. Describe the structure determination of flavonoids, specificity and intensity of absorption signal by using IR and NMR spectra. Give the example of at least two different structures.
Emit infrared light when the organic compounds in the number of frequencies to be absorbed while other frequencies transmitted without being absorbed. Infrared region of the electromagnetic spectrum lies between the visible and the radio spectrum, between 4000-400 cm-1. Infrared spectrophotometry to identify functional groups of functional groups such as converting the specific absorption in the infrared region. Typical infrared spectra for several organic compounds, so the method is appropriate for determining the structure of unknown compounds by means of comparing it against a known compound .. Nuclear Magnetic Resonance (NMR) spectroscopy is a tool available for determining the structure of organic compounds. This technique relies on the ability of atomic nuclei have properties such as a tiny magnet, and adjust to the external magnetic field. Usually used to identify or explain information about the structure of chemical compounds. The working principle of NMR is to get the core of the molecule in the same direction so that later seseuai magnetic field with the molecule will be converted into the molecular structure of the NMR spectra that can be identified.
Emit infrared light when the organic compounds in the number of frequencies to be absorbed while other frequencies transmitted without being absorbed. Infrared region of the electromagnetic spectrum lies between the visible and the radio spectrum, between 4000-400 cm-1. Infrared spectrophotometry to identify functional groups of functional groups such as converting the specific absorption in the infrared region. Typical infrared spectra for several organic compounds, so the method is appropriate for determining the structure of unknown compounds by means of comparing it against a known compound .. Nuclear Magnetic Resonance (NMR) spectroscopy is a tool available for determining the structure of organic compounds. This technique relies on the ability of atomic nuclei have properties such as a tiny magnet, and adjust to the external magnetic field. Usually used to identify or explain information about the structure of chemical compounds. The working principle of NMR is to get the core of the molecule in the same direction so that later seseuai magnetic field with the molecule will be converted into the molecular structure of the NMR spectra that can be identified.
1. Identify patterns of anthocyanin spectrum using spektrofoto-meter UV-Vis way mangosteen rind extract spotted on thin layer chromatography plates (TLC) preparative.
On the results of UV-Vis spectra preparative TLC results, the peak wavelength at 279 nm maximum, 317 nm and 525 nm. Peak at a wavelength of 279 nm and 525 nm exhibit of antosianin.Kandungan Anthocyanin compounds in mangosteen skin including sianidin types (3, 5,7,3 ', 4')-3-glucoside with a maximum wavelength of 275 nm and 523 nm.
2. Identification of Flavonoid Compounds in Leaves Katu
Methanol solution of the compound gave absorption bands I 344 nm and 269 nm bands II. The existence of dark purple spots under ultraviolet light turned green and yellow after being given the ammonia vapor, thus leading to flavone compounds, kalkon or flavonol.Pada addition of sodium hydroxide bands I batokromik shift by 62 nm and no degradation in strength, indicating OH -4 '. addition of sodium asetatmenunjukkan the OH-7 and oxygenation may be there at 6 or 8, this can be seen by the shift of bands II less than 5 nm. Batokromik 4 nm shift in the band II with the addition of sodium acetate and boric acid showed ortho dihydroxy at ring A (6, 7 or 7, 8). No change in maximum absorption bands II with the addition of aluminum chloride and hydrochloric acid menunjukkankemungkinan the OH-5 with a group prenil the C atom number 6.Dari the ultraviolet spectral data of compounds SA-DE-4 leading to flavonol compounds substituted with OH-3 and OH substitution located on the C atom position number 5, 7, 8, 4.
3. In the isolation of alkaloids, in the early stages of acid or base required conditions. Explain the basis of the use of reagents, and give examples of at least three kinds of alkaloids.
isolation alkaliod usually on acidic or alkaline because alkaline and acidic conditions used to maintain the state to allow the isolation nemar really going well. Alkaloids tend to be alkaline and volatile. While in acidic conditions used to produce alkaloids in the form of salt and not easily evaporate. In the isolation of nicotine 25 grams chopped dried tobacco leaves that have been wrapped in filter paper inserted into the Soxhlet apparatus, extraction using 300 mL of methanol for 7 hours.
isolation alkaliod usually on acidic or alkaline because alkaline and acidic conditions used to maintain the state to allow the isolation nemar really going well. Alkaloids tend to be alkaline and volatile. While in acidic conditions used to produce alkaloids in the form of salt and not easily evaporate. In the isolation of nicotine 25 grams chopped dried tobacco leaves that have been wrapped in filter paper inserted into the Soxhlet apparatus, extraction using 300 mL of methanol for 7 hours.
The sample used is 100 grams so the extraction is done 4 times. Extract / filtrate resulting solution is evaporated until the resulting filtrate concentrated or only 10% of the original volume of the concentrated solution is poured into the erlenmeyer flask and acidified with 2 M H2SO4 at 25 mL. The solution was stirred with a magnetic stirer to be homogeneous. The solution was tested with litmus paper to red. Then the solution was extracted with chloroform 25 mL 3 times a separating funnel. The resulting extracts were tested with reagents undercoat Dragendorf, if there is a positive alkaloid orangepenambahan acid deposition in isolation to form a salt of nicotine is nicotine in the form of crystals, because the purification of solids will be easier than the liquid. While the base is neutralized by addition to yield the free base, because that can be extracted by organic solvents is in the form of free base nicotine. Isolation is the same as occurs in isolation opium and cocaine.
4. Describe
the relationship between biosynthesis, methods of isolation and
structural determination of compounds of natural ingredients. Give an example.
Biosynthesis and structure determination methods of insulating compound of natural ingredients have a relationship with each other. Where Biosynthesis it is a performance of two or more existing eleman integration to produce a new result. These compounds widely used in the biosynthesis results everyday life. To obtain compounds contained in a plant / process isolation beings do. So is the isolation in which in isolation is mentioned separation of a desired compound from a sample through a certain process and treatment. Isolation results obtained later in the identification of the structure through the UV, IR, MS or NMR. With the objective of identifying the type / name of the resulting compounds.Example: The process of biosynthesis of the terpenoid compounds through mevalonic pathway. At this stage in the end produce isopentenyl pyrophosphate (IPP) and dimethyl allyl berisomerisasi a pyrophosphate (DMAPP). After that it will react to produce geranil pyrophosphate (GPP) and farnesil pyrophosphate (FPP), which are precursors to the formation of compounds derived terpenoids.
Process Isolation done to take the desired compound, compound triterpene example of a sample plant / living creatures that papaya seeds. With the stage: Papaya seeds are white dipped in hot ethanol and then crushed and dried. A total of 500 g dried papaya seed powder was extracted using the solvent n-hexane. The extract obtained was evaporated with a rotary vacuum evaporator to obtain a thick n-hexane extract. Extracts were tested phytochemical thick with Liebermann-Burchard reagent in order to make the existence of triterpenoids. Extract positive viscous triterpenoid separated by column chromatography. Prior to separation by column chromatography, eluent first election by TLC technique. The results of the separation column chromatography (silica gel 60, n-hexane: ether: ethylacetate: ethanol (2:3:3:2)) of the same group were combined and divided into fractions. Each group was tested for triterpenoid fraction. Positive fractions containing triterpenoid with a single stain followed by TLC purity test with some mixed eluent. If the stain still produce the fraction can be considered as relatively pure isolates TLC. Relatively pure isolates were then analyzed by Ultra violet-visible spectrophotometer and Infrared.
Biosynthesis and structure determination methods of insulating compound of natural ingredients have a relationship with each other. Where Biosynthesis it is a performance of two or more existing eleman integration to produce a new result. These compounds widely used in the biosynthesis results everyday life. To obtain compounds contained in a plant / process isolation beings do. So is the isolation in which in isolation is mentioned separation of a desired compound from a sample through a certain process and treatment. Isolation results obtained later in the identification of the structure through the UV, IR, MS or NMR. With the objective of identifying the type / name of the resulting compounds.Example: The process of biosynthesis of the terpenoid compounds through mevalonic pathway. At this stage in the end produce isopentenyl pyrophosphate (IPP) and dimethyl allyl berisomerisasi a pyrophosphate (DMAPP). After that it will react to produce geranil pyrophosphate (GPP) and farnesil pyrophosphate (FPP), which are precursors to the formation of compounds derived terpenoids.
Process Isolation done to take the desired compound, compound triterpene example of a sample plant / living creatures that papaya seeds. With the stage: Papaya seeds are white dipped in hot ethanol and then crushed and dried. A total of 500 g dried papaya seed powder was extracted using the solvent n-hexane. The extract obtained was evaporated with a rotary vacuum evaporator to obtain a thick n-hexane extract. Extracts were tested phytochemical thick with Liebermann-Burchard reagent in order to make the existence of triterpenoids. Extract positive viscous triterpenoid separated by column chromatography. Prior to separation by column chromatography, eluent first election by TLC technique. The results of the separation column chromatography (silica gel 60, n-hexane: ether: ethylacetate: ethanol (2:3:3:2)) of the same group were combined and divided into fractions. Each group was tested for triterpenoid fraction. Positive fractions containing triterpenoid with a single stain followed by TLC purity test with some mixed eluent. If the stain still produce the fraction can be considered as relatively pure isolates TLC. Relatively pure isolates were then analyzed by Ultra violet-visible spectrophotometer and Infrared.
