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Synthesis and Cytotoxicity Evaluation of Novel C-3 Aminocarbamate Pregnenolone Derivatives
(2025-03-06)
Charoenying, Patchanee
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Chotsaeng, Nawasit
Cancer is one of the leading causes of death worldwide. There are many ongoing studies in the search for new treatments or drugs to combat cancer. Similarly, in this research, twelve 3-aminocarbamate pregnenolones (2a–2l) were designed, synthesized, and evaluated for their cytotoxicity against five cancer cell lines: Human hepatocellular carcinoma (HepG2), Human colon adenocarcinoma (HT-29), Human oral cavity carcinoma (KB), Human breast adenocarcinoma (MCF-7), Murine leukemia (P388), and one normal cell line, African green monkey kidney fibroblast (Vero), using the MTT assay. Notably, 3-aminobenzylcarbamate pregnenolone (2b), 3-diaminoheptylcarbamate pregnenolone (2f), and 3-diaminopropanolcarbamate derivative (2i) were the most potent against these cancer cell lines. Specifically, for P388 cell lines, these compounds were more potent than the positive control drug, vinblastine sulfate salt. Results from the SAR study demonstrated that the length of the alkyl chain of diaminocarbamate derivatives was crucial for their anticancer properties. These findings will be useful in the future research and development of anticancer drugs.
1
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Assessment of Electromagnetic Field Exposure from Multiple Sources Simultaneously in the High-Frequency Range Based on Safety Standards
(2025-01-01)
Chutchavong, Vanvisa
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Aroonmitr, Pongsathorn
This study presents a method for evaluating electromagnetic field (EMF) exposure from multiple sources operating simultaneously across a wide range of frequencies, based on the guidelines defined by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) in its 2020 publication. The proposed approach adopts the normalized exposure ratio, which combines the exposure values from all relevant sources and frequency bands. A key issue addressed in this study is the lack of standardized measurement methods for absorbed power density (S<inf>ab</inf>) in high-frequency bands above 10 GHz, despite the existence of defined exposure limits. A comparison reveals that the difference between the limits for S<inf>ab</inf> and incident power density (S<inf>inc</inf>) for the general public is relatively small when compared to the gap between the general public and occupational exposure limits. Therefore, the use of S<inf>inc</inf> is proposed as a temporary surrogate for S<inf>ab</inf> in frequency ranges where direct measurement is not yet feasible. This approach enables comprehensive exposure assessment from multiple sources under both near-field and far-field conditions. It also serves as a practical alternative while S<inf>ab</inf> measurement techniques for high-frequency applications such as 5G, WiGig, and next-generation wireless technologies are still under development.
1
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Synthesis and Anti-Plant Pathogenic Fungal Activity of Flavokawain-Derived Flavones and Related Flavones Against Rhizoctonia solani
(2024-01-03)
Onnom, Panuwat
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Chotpatiwetchkul, Warot
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Meesin, Jatuporn
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Thapanapongworakul, Pilunthana
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Kittiwongwattana, Chokchai
Flavones are organic compounds in the flavonoid family that have a diverse range of biological functions. In this research, many flavones with various substituents were designed and synthesized from flavokawains A, B, and C, and their chalcone derivatives via an iodinecatalyzed oxidative cyclization process. All synthetic flavones were investigated for antifungal activities against Rhizoctonia solani, a plant pathogenic fungus. At 400 µg, most of the substances did not inhibit the tested species and R. solani growth was inhibited by only obromoflavone (40) by 74.88±0.91%. This indicated that the detrimental effect of flavones depends on the type and position of substituent, with the ortho bromo group showing the most promise. The molecular docking study on the succinate dehydrogenase (SDH) enzyme revealed that the bromophenyl moiety (ring B) is a key molecular substructure of the flavone fungicide. The findings of this study will be used to develop novel plant pathogenic fungicides.
2
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Design, Synthesis, and Structure-Activity Relationship (SAR) Studies of Ketone-Isobenzofuranone Hybrid Herbicides
(2023-02-01)
Chotsaeng, Nawasit
Thirty-five ketone-isobenzofuranone hybrids (1–35) were designed, synthesized, and evaluated for their herbicidal activity against Chinese amaranth (Amaranthus tricolor) and barnyard grass (Echinochloa crus-galli). The structure-activity relationship (SAR) results revealed that the position and type of substituent were crucial for activity. The o-substituted derivatives outperformed the m- and p-substituted derivatives. Compounds with strong electron-donating groups (OH, OMe) had low activity, while those with heterocycles (N-methylpyrrole, furan, and thiophene) had a moderate herbicidal effect. Compounds with a weak electron-donating group (Me) and weak, moderate, and strong electron-withdrawing groups (F, Cl, Br, and NO<inf>2</inf>) showed promising herbicidal activity. Among these, the o-F substituted compound (20) was the most effective against Chinese amaranth, and the o-Cl substituted compound (23) was the most potent against barnyard grass. This is the first time the herbicidal potential of ketone-isobenzofuranone hybrids has been studied. The discovery of current chemical clues would be beneficial for the development of novel herbicides.
3
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Design, synthesis, and evaluation of the anticancer activity of 2-amino-aryl-7-aryl-benzoxazole compounds
(2017-11-01)
Khajondetchairit, Patcharaporn
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Phuangsawai, Oraphan
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Suphakun, Praphasri
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Rattanabunyong, Siriruk
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Choowongkomon, Kiattawee
A series of 2-amino-aryl-7-aryl-benzoxazole derivatives have been designed, synthesized, and evaluated as anticancer agents. Fourteen of the compounds exhibited cytotoxic effects toward human A549 lung cancer cells. We found 12l was the most potent with an EC<inf>50</inf> of 0.4 μm, equivalent to the anticancer drug doxorubicin, but had low selectivity following cross screening in monkey kidney Vero cells. Eight of the most potent or most selective compounds were further profiled in additional cell lines (MCF7, NCI-H187, and KB) to better understand their cytotoxic activity. Only compound 12l had a measurable EC<inf>50</inf> in a single cell line (3.3 μm in the KB cell line). Taken together, this data suggest the series as a whole display specific cytotoxicity toward A549 cells. Cheminformatics searches pointed to JAK2 as a possible target. A subset of compounds assayed at this target showed IC<inf>50</inf>s ranging from 10 to 0.08 μm; however, no clear correlation between JAK2 potency and A549 cytotoxicity was observed.
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Analysis of heat transfer and specific absorption rate of electromagnetic field in human body at 915 MHz and 2.45 GHz with 3D finite element method
(2012-12-01)
Suwansin, W.
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Phasukkit, P.
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Pintavirooj, C.
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Sanpanich, A.
This paper presents 3D finite element analysis for heat transfer and specific absorption rate of electromagnetic field in human body at 915 MHz and 2.45 GHz. The purpose of this research is to study the effects and harmfulness of leakage electromagnetic field to organ in living tissue. We propose a simulation of microwave radiation by using a finite element method (FEM) to our system for studying heat transfer and specific absorption rate of electromagnetic field in multi-organs living tissue. Electromagnetic wave distribution source in our system was designed as a microstrip type and placed at 5 cm from multi-organs living tissue model. As a preliminary, leakage power was assumed at 100 W and exposure time was 1800 s. The result from finite element method show distribution of electromagnetic field in 3D air space of multi-organs tissue model , specific absorption rate (SAR) and temperature. The SAR value will be followed the standard of ICNIRP (1998) and the results at 915 MHz and 2.45 GHz shown that maximum temperature in organs are different if frequencies different, in 3D model can be obtained every point of view and benefit for development protection system in near future. ©2012 IEEE.
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SAR segmentation using anisotropic diffusion
(2005-12-01)
Intajag, Sathit
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Tipsuwanpon, Vittaya
Speckle effects are commonly observed in a synthetic aperture radar (SAR) image, which applies in many land applications, such as agriculture or forestry. However, although the human eye is able to derive the meaningful information from the SAR image, automatic processing is very difficult to distinguish the objects in the images because of the noise effect present in the image. This paper presents a segmentation method of the SAR images, which uses an anisotropic diffusion algorithm with an inherence region-growing algorithm. Anisotropic diffusion is modified in logarithmic domain to remove the speckle noise and to identify the homogeneous regions in ERS and JERS satellite data. The modified diffusion method is formulated with a tensor technique, varying with both the location of a pixel in the image and the orientation of the local image geometry vicinity the pixels. In our algorithm, SAR images are transformed into logarithmic domain and using the modified anisotropic diffusion to grow the homogeneous regions in the noise environment; consequently, the segmented image in the logarithm domain is converted to the intensity domain by an exponential function. On the other hand, our diffusion algorithm can stop itself by a standard deviation to mean criteria. Simulation results on the satellite images are provided to indicate the effectiveness of the proposed method when used to remove the effects of speckle noise almost as well as that of the additive noise. The evaluation of the proposed method employs the theoretical gain in equivalent numbers of looks (ENL). © 2005 SICE.
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Speckle reduction using fuzzy morphological anisotropic diffusion
(2005-12-01)
Easanuruk, Somchai
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Mitatha, Somsak
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Intajag, Sathit
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Chitwong, Sakreya
One of important tasks of radar image processing is reducing speckle noise as preprocessing to enhance preformance of other processing such as segmentation, classification, etc. In this paper, we then apply the fuzzy morphology together with anisotropic diffusion to reduce speckled noise of SAR image. Anisotropic diffusion is designed based on additive noise model, but the form of speckled image is in multiplicative speckle model. To transform additive noise model into multiplicative speckle model, logarithmic transformation is then used. Our algorithm performs in log-domain. Finally, despeckled image being in log-domain is converted into spatial domain by using exponential transformation. Simulated image as speckled image is performed with our algorithm to show and compare results with recent reports in term of both signal to noise ratio (SNR) and the equivalent number of looks (ENL). Also, real SAR image is performed to confirm results in term of ENL only. Results from our experiment are shown that de-speckled image can smooth out in homogeneous area and preserve edge in heterogeneous area. Both visual image and numerical results are used to show all results. © 2005 IEEE.

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