Name :
liza Anggraeni
NIM :
RSA1C1100012
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.
Answer:
In general, the biosynthesis of terpenoids with the
three basic reactions
are:
· The establishment of active isoprene derived from acetic acid via mevalonic acid
· Pengganbungan head and tail of two isoprene units to form mono-, seskui-, di-, Sester-and poly-terpenoid
· Incorporation of the tail and the tail unit C-15 or C-20 produces triterpenoid and steroid
The mechanism of the reaction steps of terpenoid biosynthesis is activated by acetic acid as coenzyme A did produce acid Claisen type condensation asetoasetat.
Compounds produced by the condensation of acetyl coenzyme A did produce aldol type branched carbon chains as found in mevalinat acid. subsequent reactions are phosphorylation, elimination of phosphoric acid and decarboxylation produces isopentenyl pyrophosphate (IPP), which later became berisomerisasi Dimethyl allyl pyrophosphate (DMAPP) by enzyme isomerase. IPP as active isoprene units joined head to tail with DMAPP and this merger is the first step of the polymerization of isoprene to produce terpenoids.
This merger occurs because electrons attack the double bond carbon atoms of IPP to DMAPP a shortage of electrons followed by removal of pyrophosphate ions are produced geranil pyrophosphate (GPP) is an intermediate for all monoterpenoid compounds.
The merger between the unit next IPP and GPP by the same mechanism produces Farnesil pyrophosphate (FPP), which is an intermediate for all compounds seskuiterpenoid. diterpenoid compounds derived from geranil-geranil Pirofosffat (GGPP) derived from the condensation between one unit of IPP and GPP by the same mechanism.
· The establishment of active isoprene derived from acetic acid via mevalonic acid
· Pengganbungan head and tail of two isoprene units to form mono-, seskui-, di-, Sester-and poly-terpenoid
· Incorporation of the tail and the tail unit C-15 or C-20 produces triterpenoid and steroid
The mechanism of the reaction steps of terpenoid biosynthesis is activated by acetic acid as coenzyme A did produce acid Claisen type condensation asetoasetat.
Compounds produced by the condensation of acetyl coenzyme A did produce aldol type branched carbon chains as found in mevalinat acid. subsequent reactions are phosphorylation, elimination of phosphoric acid and decarboxylation produces isopentenyl pyrophosphate (IPP), which later became berisomerisasi Dimethyl allyl pyrophosphate (DMAPP) by enzyme isomerase. IPP as active isoprene units joined head to tail with DMAPP and this merger is the first step of the polymerization of isoprene to produce terpenoids.
This merger occurs because electrons attack the double bond carbon atoms of IPP to DMAPP a shortage of electrons followed by removal of pyrophosphate ions are produced geranil pyrophosphate (GPP) is an intermediate for all monoterpenoid compounds.
The merger between the unit next IPP and GPP by the same mechanism produces Farnesil pyrophosphate (FPP), which is an intermediate for all compounds seskuiterpenoid. diterpenoid compounds derived from geranil-geranil Pirofosffat (GGPP) derived from the condensation between one unit of IPP and GPP by the same mechanism.
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.
Answer:
1. IR spectra katecin
2. IR spectra Quecetin
Spectroscopic nuclear magnetic resonance (NMR) is a technique that snagat both in determining the structure of organic compounds. NMR spectroscopic properties associated with magnetic core. Determination of compounds will be obtained using the NMR overview nature of the core differences that exist to predict the location of the nuclei in the molecule.
1. Quercetin NMR spectrum
2. NMR spectrum katecin
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.
Answer:
Alkaloid is an
alkaline compound that contains one or more nitrogen atoms and usually a cyclical
system. Alkaloids mengandungatom carbon, hydrogen, nitrogen, and usually contains
many alkaloids oksigen.Senyawa contained in the roots, seeds, wood and leaves of
plants as well as from animals. Alkaloid compounds is a result of the metabolism
of plants and used as a backup for the synthesis of proteins. Uses of plant alkaloids
is as protective of pests.
Alkaloids usually
isilasi the extraction method, the solvent is usually water in acidify. This solvent
will be able to dissolve the alkaloids as its salt. As for the alkalinize alkaloid-containing
plant materials using sodium carbonate. Then later in the organic solvent extraction
with chloroform or ether.
example:
1. Purification nikotina compounds, namely isolation through its concentration by basify solution first. By using this technique the alkaloid will evaporate and his next in purified by distillation method. This is because these compounds are not heat resistant.
2. While I get the alkaloid from the acidic solution by the method penjerapan Lloyd method. Alkaloids which can then elution and in endapkan using reagents mayer. Then the precipitate formed separated using ion exchange chromatography method.
3. Nicotine can be purified by steam
distillation from the basified solution. Solution in water that is acidic and
contains alkaloids and alkaloid diekstraksim can basified with an organic
solvent, so that neutral and acidic compounds are readily soluble in water left
in the water.
4. Describe the relationship between biosynthesis, methods of
isolation and structural determination of compounds of natural ingredients.
Give an example.
Answer:
Biosynthesis, isolation and structure determination methods are important things needed to study these compounds in natural materials. Thirdly it is certainly intertwined with each other. Biosynthesis of an overall process of formation of compounds of natural ingredients that only lasted in living things. This process occurs in the presence of starting material, and requires ATP, and usually involve certain enzymes. In the biosynthesis of these different types of reactions occur to produce such compounds. By studying the biosynthesis of these compounds produced as well, then we can know the properties of these compounds are natural materials, so we can design an isolation method based on the nature and possible reactions to extract. For example, we can choose a suitable solvent and other treatments to obtain pure substances. Once isolated, the next bunch of knowledge-knowledge that has been known in advance, we can carry out the procedure of determining the structure of the compound, for example by spektoskopi NMR, UV-vis, IR and MS. Data from these spectra we can determine the structure of its functional groups, the number of atoms and molecular mass. And we can interpret the biosynthesis and isolation of compounds. By knowing the specific structure of the compound, then we will know the properties well.
For example, the biosynthesis of these compounds are known flavonoid phenolic compounds, it is of its nature, we can do the extraction with solvents such as petroleum ether, chloroform, n-butanol and methanol, and know the reactions that may occur by analyzing its structure.
