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800x600 Two mixture s of flavanoid compounds ( 1 and 2 ), a mixture of catechin ( 1a ) and epicatechin ( 1b ) , and a mixture of gallocatechin ( 2a ) and epigallocatechin ( 2b ) , were isolated from the active fraction of the stem bark of Aglaia elliptica methanol extract. The chemical structure of the compounds w as identified with spectroscopic data , including UV, IR, NMR ( 1 H, 13 C, DEPT 135°, HMQC, HMBC, 1 H- 1 H COSY) , and MS, and additionally compared with previously reported spectral data. All compounds were evaluated for their cytotoxic effects against P-388 murine leukemia cells. Compound 2 showed cytotoxicity against the P-388 murine leukemia cell , with an IC 50 value of 7.79 µg/mL, but compound 1 wa s found not to be active ( more than 100 µg/mL ) . Normal 0 false false false EN-ID X-NONE X-NONE

A new propylcholesterol-type steroid, namely (22E,24S)-24-propylcholest-5en-3α-acetate (1), has been isolated from the stembark of Aglaia angustifolia (Miq.). The structure of 1 was determined on the basis of spectroscopic data including 1D- and 2D-NMR as well as high resolution mass spectroscopy analysis. Compound 1 showed weak activity against the MCF-7 breast cancer cell line.

SCAP1 is a pentapeptide isolated from the hydrolysate of oyster (Saccostrea cucullata), which has antioxidant and anticancer properties. This study aims to find a novel strategy to obtain antioxidant peptide SCAP1 (Leu-Ala-Asn-Ala-Lys) through chemical synthesis. This study reports the first synthesis of SCAP1 through the solid phase peptide synthesis (SPPS) method with Fmoc strategy on 2-chlorotrityl chloride resin. A HATU-HOAt coupling reagent was employed in all amide bond formations and 95% TFA in water was employed to release the desired peptide from the solid support. The crude peptide was purified using successive preparative-RP-MPLC and RP-HPLC to obtain the pure peptide. The synthesized peptide was confirmed by mass spectrometry, showing a correct molecular ion peak at m/z 516.3143 (M+H)+, referring to the desired SCAP1. 1H-NMR spectra of the peptide revealed protons signals consistent to the structure of SCAP1. During the synthesis, the coupling between Ala and Asn(Trt) was not straightforward, which led to a low yield of the final product. The use of Trt-based Asn was not a suitable option, as it could cause aggregation during the synthesis, eventually leading to a poor yield of the final product. SCAP1 was obtained as a white solid with a percent yield of 8.28%.

Lesmana R, Goenawan H, Tarawan VM, Setiawan I, Hidayat A, Supratman U. 2019. Short Communication: Optimazing culture and differentiation L6 cell, C2C12 cell and primary myoblast cells culture. Cell Biol Dev 3: 51-54. Alteration in skeletal muscle function and structure can be as consequence of many different chronic diseases, drug treatment or physical activity. Understanding molecular mechanism of skeletal muscle diseases or adaptation process will be very important and beneficial. Most of the case of problem, example ; during aging, imbalance between anabolic and catabolic processes could initiate a decrease muscle mass and change its fiber structure. Unfortunately, there is no suitable animal model for study and some point, and development of animal model is time consuming. To study and elaborate mechanism of disease, drug target, and hormonal effects in skeletal muscle which is not easy and tricky, skeletal muscle culture is a good model of study. In vitro system utilizing 2 types of cell line which is derived from mouse (C2C12 myoblast cells) and derived from rat (L6 myoblast cells are a promising method to study molecular biology properties of muscle. Another establishement technique is using mixed and isolated single fiber primary myoctes culture.

Exumolides A and B are two cyclodepsipeptides that was previously isolated from marine fungus. Both peptides were synthesized using a combination of solid- and solution-phase method. The linear precursor was synthesized through solid-phase method on 2-chlorotrityl resin with standard Fmoc strategy. The hydroxy acid, (S)-2-hydroxy-4-methylpentanoic acid (Hmp), was prepared from its precursor l -leucine, and attached on the resin with a double-coupling protocol. The depside bond formation that was carried out at the end of the coupling process, was beneficial, particularly, in the blockage of the diketopiperazine formation during Fmoc deprotection. The cyclic product was obtained through HATU-based cyclisation. Exumolides A and B were successfully synthesized with overall yields of 4.12% and 6.39%, respectively.

SCAP1 ( S accostrea Cucullata Antioxidant Peptide 1 ) dengan urutan asam amino LANAK (Leu-Ala-Asn-Ala-Lys) merupakan pentapeptida yang diisolasi dari hidrolisat tiram dan diketahui memiliki aktivitas antioksidan dengan scavenging radikal DPPH sebesar 83,79 ± 0,53%. Peptida ini telah berhasil dibuat dengan metode sintesis peptida fase padat dengan persen rendemen 8,28%. Rendahnya persen rendemen yang diperoleh disebabkan karena adanya dua residu Ala serta 1 residu Asn yang dapat menyebabkan agregasi. Nilai loading resin yang terlalu besar juga menjadi salah satu penyebab terbentuknya agregasi karena loading resin dilakukan selama 15 jam. Penelitian ini bertujuan untuk menyintesis senyawa SCAP1 dengan pengurangan nilai loading resin . Untuk meningkatkan persen rendemen dari penelitian sebelumnya, pada penelitian ini dilakukan optimasi sintesis terhadap SCAP1. Sintesis dilakukan dengan pengurangan nilai loading resin dengan cara mempersingkat waktu loading resin menjadi 4 jam. Senyawa SCAP1 hasil sintesis memiliki massa crude sebesar 119,5 mg dan berhasil dimurnikan menggunakan RP-HPLC preparatif dengan massa murni 10,6 mg dan rendemen 16%. Penelitian ini menunjukkan bahwa pengurangan loading resin meningkatkan rendemen SCAP1 dari 8,28% menjadi 16%.

Characterization of the compound formed in the reaction between the ligand di-n-butyldithiophosphoric acid (DBDTP) and gadolinium(III) ion, and a prediction of the possible molecular structure of the synthesized compound, using molecular modelling have been carried out. Ultraviolet spectra of the resulted compound showed a bathochromic shift from 197.3 to 210.0 nm, due to the formation of Gd-S bonds. Infrared spectra of the compound showed absorptions at 1,494 and 1,394 cm-1, probably due to the in-plane vibration of Gd-S bonds. Mass spectra of the compound showed a peak at an m/z of 919.632, which corresponds to the calculated molecular mass of [Gd(DBDTP)3(H2O)2]. X-ray powder diffraction measurements showed that the compound had a hexagonal shape with the lattice parameters a = 9.97 and c = 9.09 A. From the experimental results, including those of molecular modelling, it can be drawn a conclusion that the complex molecule consisted of one gadolinium atom, which bound three di-n-butyldithiophosphate and two water ligand molecules.

Two flavanoid compounds, catechin ( 1 ) and epicatechin ( 2 ), have been isolated from the stembark of Chisocheton pentandrus . The chemical structure of compounds 1 and 2 were identified byspectroscopic data including, UV, IR, NMR ( 1 H, 13 C, DEPT 135°, HMQC, HMBC, 1 H- 1 H COSY) and MS and by comparing with previously reported spectral data. Compounds 1 and 2 , were isolated in this plant for first time and showed no cytotoxic activity against MCF-7 breast cancer cells.

PyBOP (benzotriazol-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate) was found as a good coupling reagent in the solid-phase synthesis of a tetrapeptide, OH-Pro-Leu-Ala-Ile-NH21. The peptide was chosen as the target of synthesis due to its bioactivity as an antibacterial agent. The synthesis was carried out on solid support, 2-chlorotrityl chloride resin with Fmoc strategy. Proline was selected as the first amino acid to be attached on the resin that was followed by the attachment of leucine, alanine and isoleucine. In the synthesis, Fmoc deprotection step was undertaken by taking advantage of 20% piperidine in DMF and coupling reaction was done by the addition of amino acid and PyBOP in a mixture of dichloromethane and DMF (1:1) and in the presence of basic DIPEA. The analytical RP-HPLC of the final product showed a single peak at 22.0 minutes (20-90% of acetonitrile in water with 0.1% of TFA during 30 minutes), indicating that each coupling could give a good coupling performance that resulted in a...

Tetrapeptide, OH-Pro-Ala-Gly-Tyr-NH2, was successfully synthesised on 2-chlorotrityl chloride resin by taking advantage of PyBOP (benzotriazol-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate) as coupling reagent. The selection of the peptide as the target of synthesis was due to its interesting bioactivity as antioxidant. The synthesis was undertaken with Fmoc strategy, where Fmoc-proline was added onto the resin at the first place. It is known from the literature that proline can resist from rasemisation when it was attached on the resin at the first time. Fmoc deprotection step was carried out by employing 20% piperidine in DMF and the reaction mixture was shaken for 30 minutes. Once the proline attached, the next step was to attach amino acids, alanine (Ala), glycine (Gly) and tyrosine(Tyr), subsequently onto the resin until tetrapeptidyl resin was constructed on the resin. Hydroxyl group of Tyr was protected with t-butyl, which is TFA-labiled. Coupling reaction was undertaken by mixing the amino acid and PyBOP in a mixture of dichloromethane and DMF (1:1) and in the presence of basic DIPEA. Resin cleavage step was carried out by using 95% TFA in water, where t-butyl protecting group on the side chain of Tyr was cleaved at the same time. The analytical RP-HPLC of the final product showed a single peak at 21.9 minutes (20-90% of acetonitrile in water with 0.1% of TFA during 30 minutes), indicating that each coupling has given a good coupling performance and resulting in a pure product. The desired product showed the correct molecular weight with m/z 407.2 [M+H]+ and 429.2 [M+Na]. DOI: http://dx.doi.org/10.15408/jkv.v0i0.4055

α-Hydroxyisovaleric acid (Ac-Hiv) and α-acetyloxyisovaleric acid (Ac-Hiv) have been successfully synthesized through a diazotisation of amino acid using sodium nitrite with the catalyst of sulfuric acid and acetic acid, respectively. In the synthesis of Hiv, Zubia et al. (2005) mentioned that 3 equivalents of sodium nitrite for the reaction gave the hydroxy acid with a good yield. However, Cohen-Arazi et al. (2008) described that 6 equivalents of sodium nitrite resulted the highest yield. In present study, a variation of equivalents of sodium nitrite (3, 4, 5, 6 eq.) were trialed for the same method of synthesis. Through several experiments, we found that 6 equivalents of sodium nitrite were the best portion among all. This finding was applied into the synthesis of protected Hiv (Ac-Hiv) that was previously reported by Maharani et al. (2017) giving 63% yield when 3 equivalent of sodium nitrite was employed. By increasing the equivalent of sodium nitrite into 6 equivalents, the Ac-Hiv can be synthesized with an improved yield (71%).

A new synthetic analog of bufadienolide, methyl isobryophyllinate A (1), and a known synthetic analog, methyl isobersaldegenate-1,3,5-orthoacetate (2), were obtained by methanolysis of bryophyllin A (3) and bersaldegenin-1,3,5-orthoacetate (5) in basic solution. Structure-insecticidal activity relationship studies revealed both orthoacetate and α-pyrone moieties seemed to be essential structural elements for exhibiting insecticidal activity, whereas oxygenated substituents in the C ring enhanced the insecticidal activity against the third instar larvae of silkworm (Bombyx mori).

Aureobasidins are a family of cyclodepsipeptides have antifungal properties. They were isolated from the black yeast Aureobasidium pullulans R106 and over 30 derivatives have been successfully characterized. There are few publications reporting the total synthesis of aureobasidins. The limited reports of the synthesis of the aureobasidin derivatives are due to the difficult access to the preparations of precursors. The aim of this research is to synthesise a precursor of aureobasidin B, t-butyl (2R)-hydroxyisovalerate (t-Bu-Hiv), that is prepared for the total synthesis of aureobasidin B. The synthesis of AbB is planned to be undertaken by using a solid phase method, so the ester formation between t-Bu-Hiv and the Fmoc-β-hydroxymethylvaline will be carried out in solution phase to form depsidipeptide. The t-butyl group was used as protecting agent that is due to the straightforward elimination of the protecting group from the Fmoc-depsidipeptide. The t-Bu-Hiv acid was prepared from D-valine through diazotisation to form (2R)-acetyloxyisovaleric acid in 62.7% yield. Product of the first step was then protected by t-butyl group by using Boc-anhydride in t-butanol to give t-butil (2R)-acetyloxyisovalerate in 44% yield. In the last step, the acetyloxy group was eliminated by using potassium carbonate in methanol/water to give the desired product, t-Bu-Hiv in 33.5% yield. The t-Bu-Hiv is ready to be combined with Fmoc-β-hydroxymethylvaline to result in depsidipeptide that will be attached to the resin in the total synthesis of AbB. Each stage of this synthesis was controlled by thin layer chromatography and all products were purified by open column chromatography. All the synthesized products were characterized by various spectroscopic techniques, including infrared spectrophotometer, mass spectroscopy (ESI-MS), 1H-NMR and 13C-NMR.

A methyl ester of L-mandelic acid was found to be an effective resolving agent for resolution of commercial DL-isoleucine. The resolution was based on Steglich esterification between methyl L-mandelate and Boc-DL-isoleucine. The two resolved isomers were easily separated by using a conventional flash-column chromatography, giving quantitatively good yields. Unfortunately, the methyl L-mandelate was found to be ineffective to resolve four stereoisomers of Fmoc- isoleucine.

A new 30-nor trijugin-type limonoid, chisotrijugin (1), has been isolated from the bark of Chisocheton cuminganus belong to the Meliaceae family. The chemical structure of 1 was elucidated by spectroscopic techniques such as UV, IR, MS, 1D and 2D NMR.