In the present study, a series of tri- and diorganotin(IV) carboxylates have been synthe sized by the reaction of tri- and diorganotin(IV) chlorides/oxides with substituted phenylethanoic acids/salts and α-alkyl cinnamic acids/salts in dry toluene under reflux condition for 8-10 h. The ligands used were 4-Methoxyphenylethanoic acid (HL 1 ), 4- Nitrophenylethanoic acid (HL 2 ), 4-Chlorophenylethanoic acid (HL 3 ), 3-Methylphenyl ethanoic acid (HL 4 ), 3-(4-Bromophenyl)-2-ethylacrylic acid (HL 5 ), 3-(4-Bromophenyl) -2-methylacrylic acid (HL 6 ), 3-(4-Chlorophenyl)-2-methylacrylic acid (HL 7 ), 3-(4- Chlorophenyl)-2-ethylacrylic acid (HL 8 ), 3-(4-Nitrophenyl)-2-methylacrylic acid (HL 9 ) and 3-(4-Nitrophenyl)-2-ethylacrylic acid (HL 10 ). The composition, coordination mode of ligands, structural confirmation and geometry assignment of the complexes in solid and in solution states were made by different analytical techniques such as elemental analysis, FT-IR, multinuclear ( 1 H, 13 C and 119 Sn) NMR, mass spectrometry and X-ray single crystal analysis. Based on these results, the ligand appeared to coordinate the Sn atom via COO moiety. The triorganotin(IV) derivatives demonstrate polymeric trigonal bipyramidal geometry in solid state and a monomeric tetrahedral structure in solution. The diorganotin(IV) dicarboxylates have shown a distorted octahedral or skew- trapezoidal geometry in solid state, however, the coordination around Sn change from six to five in solution, in most cases. The interaction of (n-C 4 H 9 ) 3 Sn(IV)L, (CH 3 ) 3 Sn(IV)L, (n-C 4 H 9 ) 2 (IV)SnL 2 and (C 2 H 5 ) 2 Sn(IV)L 2 (where L = 4-nitrophenylethanoate) with DNA was investigated by cyclic voltammetry (CV). The positive peak potential shift in CV evidenced intercalative mode of interaction of these complexes with DNA. The CV results revealed the following increasing order of binding strength: (C 2 H 5 ) 2 Sn(IV)L 2 (8.5 x 10 3 ) < (n-C 4 H 9 ) 2 Sn(IV)L 2 (1.11 x 10 4 ) < (CH 3 ) 3 Sn(IV)L (1.39 x 10 4 ) < (n- C 4 H 9 ) 3 Sn(IV)L (1.46 x 10 4 ) M -1 . The negative values of ∆G designate the spontaneity of complex-DNA binding. Most of the synthesized complexes were screened for their antibacterial and antifungal activities against various medically important bacteria and fungi. The triorganotin(IV) derivatives have strong bactericidal and fungicidal action than diorganotin(IV) complexes with few exceptions. Some of the compounds were found to have antimicrobial activity comparable or even more than reference drugs and may be used as drugs in future. Some complexes have shown higher cytotoxicity(against iiBrine shrimp) than standard drug while only compound 10 was found stronger anticancer agent against human prostate cell lines(PC-3).
شام سمے ہماری گاڑی طریق السلام پر فراٹے بھر رہی تھی ۔شدید گرمی سے لوگوں کے چہروں کو لال کر نے والا سورج بحیرہ احمر میں ڈبکی مارنے کی تیاری کر رہا تھا۔ساتھ والی نشست پر بیٹھی دکتورہ شائمہ سے میں نے پوچھا ہم کہاں جا رہے ہیں ۔اس نے کہا ’’مسجدِ صحابہ ‘‘بہت خوبصورت مسجد ہے ۔میں نے پوچھا کوئی پرانی مسجد ہے کہنے لگیں زیادہ پرانی نہیں مگر عمارت شاندار ہے ۔چند کلومیٹر راستہ طے کرنے کے بعد بلند میناروں والی مسجد صحابہ کے بلند وبالا گنبد و مینار اپنی عظمت کا احساس دلا رہے تھے ۔صحرائے سینا کی ریت کی مانند زرد بھوری مائل خشت اور ریختے سے بنی یہ مسجد ایک خوبصورت دلہن کی طرح سجی نظر آ رہی تھی ۔ دکتورہ شائمہ کے بہ قول اس مسجد کی بنیاد ۲۰۱۱ء میں رکھی گئی ۔مگر ملکی سیاسی حالات میں اتار چڑھائو کی وجہ سے تعمیراتی کام تسلسل کے ساتھ جاری نہ رہا ۔اس مسجد کا نقشہ ایک مصری آرکیٹیکٹ فواد توفیق نے بنایا ،نقشے کو ترتیب دیتے وقت فواد توفیق نے مصر پر حکمرانی کر نے والے تین مسلم ادوار فاطمی ،مملوکی اور عثمانی کو مدِ نظر رکھا ۔مسجد کے دو طویل القامت مینار اور کئی گنبد دیکھنے والوں کی آنکھوں کو خیرہ کرنے میں کوئی کسراٹھا نہیں رکھتے ، مسجد کے صحن میں سیمنٹ اور گارے سے بنے خوبصورت پانی کے جھکے ہوئے مٹکے جن میں لگی برقی موٹروں کے ذریعے قریبی گملوں اور کیاریوں میں موجود پودوں اور پھلوں کو سیراب کیے جانے کا دلکش منظر دیکھ کر سیاح اپنے موبائل کیمروں میں اس کی عکس بندی میں مصروف تھے ۔دکتورہ بسنت نے مجھ سے پوچھا کہ ’’آپ مسجد کے اندر جائیں گے ؟‘‘ میں نے کہا جی ضرور ۔انھوں نے مجھے دکتورخالد ،دکتورہ شائمہ کے...
Renowned Yemeni poet and freedom fighter Muhammad Mahmood Al-Zubairi, also known as the father of freemen, born in Sanna in 1910 in a middle class family. He was one of the Yemeni iconic revolutionaries who opposed the Imamate. He took part in the revolution in 1962, bringing about Yemen’s transition from a monarchy to a republic. He was one of the founders of the movement of liberals and the leader of opposition against the Imam’s rule. This led to his persecution and he suffered destitution and exile outside his country, settling finally in Pakistan where he had opportunity to translate the poetry of Pakistan’s national poet, Muhammad Iqbal into Arabic. Finally, in 1962, when the revolution against the Imam erupted in Yemen, he went back to his country and became the minister of education. He fallen victim to the royalist forces in 1965 and has been regarded since as one of the Yemen’s most acclaimed martyrs. Al- zubairi published several collection of poetry. In 1978, a volume of his collected poems was published entitled Diwan al-zubairi. His work reflects a real originality of themes, ideas and method of treatment. This article discusses the literary work of Abu Ahrar Muhammad Mahmood Al-Zubairi.
We are living in a scientific age. The battlefields of today are not in the planes and deserts but in the educational institutions. Pakistan is a developing country. Advancement in the field of science and technology is the only alternative, which can embark upon an era of economic as well as social development. This advancement requires revolutionary improvement in the field of science education at all levels. Keeping in mind the importance of science education, the present research study was undertaken. The objectives of the study were: a) to find the facilities available in the school laboratory for science education at secondary level in the sample institutions. b) To identify the problems in science education program at the secondary level in the sample institutions c) to identify the shortcomings in the pre-service training of science teachers of secondary level. The study was descriptive in nature and survey type. The population of the study was all secondary school science teachers, headmasters, secondary class science students and science experts. The previous education policies, reports, plans, educational documents, research papers and books were also studied. Data were collected through questionnaires. For this purpose, three questionnaires were developed consisting of closed items designed on five-point Likert scale. The last two items in each questionnaire were open ended. One questionnaire was for the science teachers, one for the science students and one for headmasters and science experts. The items in all the questionnaires were mostly the same except that some items were removed from students’ questionnaires such as items on teachers’ pre- service training. Besides, the science teachers’ questionnaire contained items on lab facilities. The sample was randomly selected from ten districts of Punjab province. The questionnaires were administered to the respondents and their responses were statistically analyzed using chi-square test for homogeneity at 0.05 level of significance. The open-ended items were analyzed based on its frequency of occurrences which was converted in to percentages. The findings of the study were that the examination system emphasized on memorization and neglected the application of concepts. The science course content was lengthy and contained irrelevant material. The science course content did not meet the international standards nor did it fulfill the needs of individual and society. Activity oriented method was lacking in science teaching. The pre-service teachers’ training focused more on theory and less on the practical aspect of teaching. The major recommendations of the study were that the examination should equally emphasize recalling, understanding and application of knowledge. The science course content may be reviewed to bring it at par with the international level. Due weightage should be given to the internal assessment. The science teachers should make use of activity methods and should involve the students to participate actively in the class. The teachers may be trained in using modern teaching methodologies and conducting science practical at the required level. The science education program may be regularly monitored and supervised.