A new series from thieno[2,3-d] pyrimidine derivatives have been synthesized based on 2-
(ethylmercapto)-4-mercapto-6-phenyl-5-pyrimidine carbonitrile, these compounds used in the synthesis of
many pyrimidothienopyrimidine derivatives and triazolo[1″,5″:1″,6″]pyrimido[40,50:4,5]thieno[2,3-d] pyrimidine
derivatives. The chemical composition of these compounds was confirmed by 1H NMR, 13C
NMR, and MS techniques. Some of the synthesized compounds were screened for their antimicrobial and
anticancer agent. Compound (9b) showed strong effect on Aspergillus Fumigatus (RCMB 2568), Candida
albicans (RCMB 05036), Saphylococcus aureus (RCMB 010010), Bacillis subtilis (RCMB 010067), Salmonella
sp. (RCMB 010043), and Escherichia coli (RCMB 010052). Compounds (2) and (5a–k) were evaluated
for their IC50 values against two cancer cell lines (MCF-7 and HeLa cells) in the presence of Paclitaxel as
reference material. Compound (5g) showed the highest cytotoxicity against MCF-7 (IC50 values about
18.87 ± 0.2 μg/mL) cells compared with Paclitaxel (IC50 values about 40.37 ± 1.7 μg/mL). Also, compound
(5d) showed the highest cytotoxicity against HeLa (IC50 values about 40.74 ± 1.7 μg/mL) cells compared
with Paclitaxel (IC50 values about 45.78 ± 0.8 μg/mL).

This paper describes a new method to prepare organic-soluble silver nanoclusters (AgNCs) protected by thiophenol (TP) (1), 4-fluorothiophenol (4-FTP) (2) and 4-methylthiophenol (4-MeTP) (3) ligands. Those ligands was chosen to investigate the effect of the substituting group attached to the thiophenol moiety from the point of withdrawing group (fluorine atom) and donating group (methyl group) and their effect in the stability of silver clusters. The optical properties of the as synthesized silver nanoclusters exhibited a broad surface plasmon resonance (SPR) peaks at 464 nm, 474 nm and 475 nm for Ag@SPhX (X= H, F, and Me), respectively. All the three types of silver nanoclusters (1-3) are highly stable even when being exposed to air as indicated by their absorption spectra. There is almost no change in the intensity of their UV-vis absorption peaks even after 24 hours of air exposure. Therefore, we succeeded in the separation of highly stable silver nanoclusters versus the ambient oxidative condition. The morphology and particles size of the as synthesized nanoclusters were estimated by using transmission electron microscopy (TEM). It was found that, all the three types of silver clusters have a homogenous particle size distribution, with an average particle size of about 2 nm. The average chemical formula and the silver to ligand (Ag/L) ratio were calculated by thermogravimetric analysis (TGA) of the synthesized silver nanoclusters.

This paper describes a new method to prepare organic-soluble silver nanoclusters (AgNCs) protected by thiophenol (TP) (1), 4-fluorothiophenol (4-FTP) (2) and 4-methylthiophenol (4-MeTP) (3) ligands. Those ligands was chosen to investigate the effect of the substituting group attached to the thiophenol moiety from the point of withdrawing group (fluorine atom) and donating group (methyl group) and their effect in the stability of silver clusters. The optical properties of the as synthesized silver nanoclusters exhibited a broad surface plasmon resonance (SPR) peaks at 464 nm, 474 nm and 475 nm for Ag@SPhX (X= H, F, and Me), respectively. All the three types of silver nanoclusters (1-3) are highly stable even when being exposed to air as indicated by their absorption spectra. There is almost no change in the intensity of their UV-vis absorption peaks even after 24 hours of air exposure. Therefore, we succeeded in the separation of highly stable silver nanoclusters versus the ambient oxidative condition. The morphology and particles size of the as synthesized nanoclusters were estimated by using transmission electron microscopy (TEM). It was found that, all the three types of silver clusters have a homogenous particle size distribution, with an average particle size of about 2 nm. The average chemical formula and the silver to ligand (Ag/L) ratio were calculated by thermogravimetric analysis (TGA) of the synthesized silver nanoclusters.

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Here, we used the methanol-induced precipitation method to prepare and separate two size selected gold clusters protected by two enantiomers and racemic mixture of penicillamine ligand. The clusters materials were obtained by the reduction of HAuCl4∙3H2O salt with NaBH4 in the presence of L-penicillamine (L-pen), D-penicillamine (D-pen) and racemic mixture of penicillamine (rac-pen) as capping ligands. Two fractions were obtained with particles of about 1 nm and 2.6 nm, respectively. The average chemical formula was determined from thermogravimetric analysis (TGA). The optical properties of the samples were studied by three different methods: UV-vis spectroscopy, photoluminescence spectroscopy (PL) and circular dichroism (CD) spectroscopy. PL studies yielded the fluorescent properties of the samples. The main focus of this work, however, lies in the chirality of the particles. The CD spectra for gold clusters capped with one of the two enantiomers (D- or L-form) typical CD spectra were observed, no significant signals were detected for a racemic ligand mixture. Furthermore, gold clusters show quite large asymmetry factors (up to 1.3x10-3) in comparison to most other ligand protected clusters. These large factors and bands in the visible range of the spectrum suggest a strong chiral induction from the ligand to the metal core.

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The glass transition and non-isothermal crystallization
behavior of Ge20Se70Sn10 glass prepared by the
melt-quenching technique was investigated using differential
scanning calorimetry (DSC) at continuous different
heating rates. The structure and surface morphology of asprepared
and annealed samples were characterized using
X-ray diffraction (XRD) and scanning electron microscopy.
The as-prepared samples showed the amorphous
glassy nature, while the annealed ones are polycrystalline.
Furthermore, XRD phase analysis allowed us to find the
SnSe2, GeSe2, Ge4Se9 and Sn0.5 SeGe0.5 phases in the
annealed samples. According to the value of Avrami index
(n), the crystallization process of studied composition has
more than one crystal growth mechanism. In addition, the
results of DSC showed that the investigated glass has only
a single glass transition and double crystallization stages.
Furthermore, the activation energy of transition as well as
the crystallization has been determined based on different
approximation methods. In addition, the experimental DSC
data of the first and second crystallization peak were
compared with that calculated with the Johnson–Mehl–
Avrami and Sestak–Berggren SB(M, N) model. The results
revealed that the SB(M, N) model is more suitable for
describing the crystallization kinetics of studied glass.

The glass transition and non-isothermal crystallization
behavior of Ge20Se70Sn10 glass prepared by the
melt-quenching technique was investigated using differential
scanning calorimetry (DSC) at continuous different
heating rates. The structure and surface morphology of asprepared
and annealed samples were characterized using
X-ray diffraction (XRD) and scanning electron microscopy.
The as-prepared samples showed the amorphous
glassy nature, while the annealed ones are polycrystalline.
Furthermore, XRD phase analysis allowed us to find the
SnSe2, GeSe2, Ge4Se9 and Sn0.5 SeGe0.5 phases in the
annealed samples. According to the value of Avrami index
(n), the crystallization process of studied composition has
more than one crystal growth mechanism. In addition, the
results of DSC showed that the investigated glass has only
a single glass transition and double crystallization stages.
Furthermore, the activation energy of transition as well as
the crystallization has been determined based on different
approximation methods. In addition, the experimental DSC
data of the first and second crystallization peak were
compared with that calculated with the Johnson–Mehl–
Avrami and Sestak–Berggren SB(M, N) model. The results
revealed that the SB(M, N) model is more suitable for
describing the crystallization kinetics of studied glass.

The glass transition and non-isothermal crystallization
behavior of Ge20Se70Sn10 glass prepared by the
melt-quenching technique was investigated using differential
scanning calorimetry (DSC) at continuous different
heating rates. The structure and surface morphology of asprepared
and annealed samples were characterized using
X-ray diffraction (XRD) and scanning electron microscopy.
The as-prepared samples showed the amorphous
glassy nature, while the annealed ones are polycrystalline.
Furthermore, XRD phase analysis allowed us to find the
SnSe2, GeSe2, Ge4Se9 and Sn0.5 SeGe0.5 phases in the
annealed samples. According to the value of Avrami index
(n), the crystallization process of studied composition has
more than one crystal growth mechanism. In addition, the
results of DSC showed that the investigated glass has only
a single glass transition and double crystallization stages.
Furthermore, the activation energy of transition as well as
the crystallization has been determined based on different
approximation methods. In addition, the experimental DSC
data of the first and second crystallization peak were
compared with that calculated with the Johnson–Mehl–
Avrami and Sestak–Berggren SB(M, N) model. The results
revealed that the SB(M, N) model is more suitable for
describing the crystallization kinetics of studied glass.

The glass transition and non-isothermal crystallization
behavior of Ge20Se70Sn10 glass prepared by the
melt-quenching technique was investigated using differential
scanning calorimetry (DSC) at continuous different
heating rates. The structure and surface morphology of asprepared
and annealed samples were characterized using
X-ray diffraction (XRD) and scanning electron microscopy.
The as-prepared samples showed the amorphous
glassy nature, while the annealed ones are polycrystalline.
Furthermore, XRD phase analysis allowed us to find the
SnSe2, GeSe2, Ge4Se9 and Sn0.5 SeGe0.5 phases in the
annealed samples. According to the value of Avrami index
(n), the crystallization process of studied composition has
more than one crystal growth mechanism. In addition, the
results of DSC showed that the investigated glass has only
a single glass transition and double crystallization stages.
Furthermore, the activation energy of transition as well as
the crystallization has been determined based on different
approximation methods. In addition, the experimental DSC
data of the first and second crystallization peak were
compared with that calculated with the Johnson–Mehl–
Avrami and Sestak–Berggren SB(M, N) model. The results
revealed that the SB(M, N) model is more suitable for
describing the crystallization kinetics of studied glass.