Judul: Efektivitas Gugus Pelindung –Oh Fenolik Pada Floroasetofenon Dalam Sintesis 2'-Hidroksikalkon, Zat Antara Ke Kuersetin Dan Kaemferol
Abstrak: Upaya mengisolasi kuersetin dan kaemferol dari daun jambu biji merah dan daun sirsak belum berhasil mendapatkan senyawa murni. Harga senyawa murni yang tinggi juga melatari perlunya upaya menyintesis kaemferol. Sintesis dikerjakan melalui siklisasi oksidatif Algar-Flynn-Oyamada pada 2'-hidroksikalkon, yang disintesis melalui kondensasi Claisen-Schmidt senyawa floroasetofenon (2',4',6'-trihidroksiasetofenon) dengan turunan benzaldehida. Suasana basa dalam reaksi kondensasi dapat mendeprotonasi gugus –OH, sehingga gugus ini perlu dilindungi. Gugus benzil (Bn) didapati paling efektif melindungi floroasetofenon membentuk 2',4'-dibenziloksifloroasetofenon (rendemen 30%). Gugus alil dan metil memberikan rendemen lebih besar (33 dan 36%) untuk produk diproteksinya, tetapi memerlukan tahapan pemurnian yang panjang, sedangkan gugus pelindung tetrahidropiranil tidak dapat memproteksi floroasetofenon. Proteksi Bn pada senyawa turunan benzaldehida memberikan rendemen 89 dan 75% berturut-turut untuk 3,4-dibenziloksi- dan 4-monobenziloksibenzaldehida. Secara keseluruhan, 2'-hidroksikalkon terproteksi-Bn prekursor kuersetin dan kaemferol dihasilkan sebanyak 69% dan 71% dalam 2 tahap dari turunan benzaldehida.
Keyword: 2'-hidroksikalkon, gugus pelindung benzil, kaemferol, kuersetin

Judul: Efektivitas Gugus Pelindung ‒OH Fenolik pada Floroasetofenon dan 3,4- Dihidroksibenzaldehida dalam Upaya Menyintesis Kuersetin
Abstrak: Quercetin is a of flavonol compound with hydroxylated A and B rings. Synthesis of this group of compounds is commonly through condensation reaction between hydroxylated acetophenoneand benzaldehyde derivatives and needs introduction of phenolic-OH protecting groups. In this study, tetrahydropyranylether (OTHP) and benzylether (OBn) were compared for their effectiveness in protecting the 2 phenolic‒OH groups in phloroactophenone and 3.4-dihydroxybenzaldehyde as the first step in quercetin synthesis. OTHP gave a huge steric hindrance so it could not protect the phenolic-OH of phloroacetophenone. On the contrary, OBn protected phloroacetophenone and 3,4-dihydroxybenzaldehyde more effectively. Two equivalent of BnBr in dimethylformamide after 24 hours, produced 2’,4’-di-Obenzylphloroacetophenone and 3,4-bis-(benzyloxy)benzaldehyde with 48% and 55% of yield, respectively. The condensation reaction between the two protected precursors produce mixture of products predicted to contain eriodictiol chalcone Bn-protected. Oxidative cyclization of the chalcone was yet to be succeeded to failed to form tetra-O-benzylquercetin. However, the effectiveness of OBn as a phenolic-OH protective group has been successfully demonstrated in this study
Keyword: phloroacetophenone tetrahydropyranil, 3.4-dihydroxybenzaldehyde, chalchone, benzyl

Judul: Relationship between Energy· Intensity and Income per Capita: A Comparative Study on Ten Asia Pasific Countries
Abstrak: Energy availability and consumption play an important and strategic role in generating economic growth. One common measurement used in analyzing energy-GOP relationship is energy intensity, which is the amourit of energy required to produce a unit of income (GDP). This research examines relationship between energy intensity and income per capita for ten Asia Pacific countries with various economic performances over the period of 1980-2005. Using static and dynamic panel data models, energy consumption and energy intensity arc expressed as quadratic logarithmic function of income per capita, squared income per capita, and energy price. As a result, the long run coefficient of income per capita is greater than one and the long run coefficient of squared income per capita is negative. It describes that energy intensity has quadratic relationship with income per capita, and indicating a change in trend of energy intensity. This research also analyzes responses of energy consumption and energy intensity to the change of energy price and income per capita in both the short run and long run. The price elasticity is negative and very inelastic; it means the response of energy consumption with respect to the change in energy price is relatively low. However, the estimation results are also show that the income elasticity is positive but tends to decrease over time. Here, the estimated value of income elasticity varies across countries where the high income countries have lower elasticities than those of the middle-low income countries.
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