The work presented in this thesis has been divided into two parts. Part one deals with the synthesis, characterization and biological activity of some 7-substituted 6,8- dioxygenated isocoumarins and 3,4-dihydroisocoumarins. Chapter one includes general introduction, nomenclature, structural types, biosynthesis, and extensive examples on pharmacological efficacy of isocoumarins and 3,4-dihydroisocoumarins from literature. It also provides some of the most significant synthetic routes and the reactions of isocoumarins and 3,4-dihydroisocoumarins and their interconversion. The total synthesis of structural analogues of some naturally occurring bioactive isocoumarins and dihydroisocoumarins viz. Hiburipyranone, Cytogenin, Montroumarin, Scorzocreticin, Annulatomarin, Thunberginol B, starting from 3,5-dimethoxy-4-methyl homophthalic acid is the subject of Chapter two. The synthesis of 3,5-dimethoxy-4- methylhomophthalic acid from simplest precursor p-toluic acid was carried out. The substituted homophthalic acid was then converted into corresponding anhydride which was then condensed with various acyl and aroyl chlorides to afford the corresponding 3- alkyl or 3-arylisocoumarins. The isocoumarins were then converted into corresponding 3,4-dihydroisocoumarins and the latter were then demethylated to afford corresponding 6,8-dihydroxy-3,4-dihydroisocoumarins. The structures of all of the synthesized compounds were confirmed using FTIR, 1H NMR, 13 C NMR and mass spectral data. Chapter three provides the physical constants and spectroscopic data of the synthesized compounds. Chapter four deals with the biological activities of the compounds synthesized. Antibacterial activity was determined against ten different Gram positive and Gram negative bacterial strains (Micrococcus luteus, Staphylococcus aureus, Staphylococcus epidermidis, Lactobacillus bulgaricus, Escherichia coli, Klebsiella pneumonae, Pasteurella multocida, Proteus vulgaris, Pseudomonas aeruginosa and Salmonella typhi) using agar well diffusion method. In vitro antimalarial activity was performed against malarial parasite Plasmodium falciparum. The cytotoxic activity of the synthesized compounds was determined against human keratinocyte cell lines. Chapter five depicts total synthesis of a natural product 8-hydroxy-7- hydoxymethyl-6-methoxy-3,4-dihydroisocoumarin (Stellatin) isolated from mycelium of Aspergillus variecolor. The structures of the precursor compounds and the Stellatin were determined by FTIR, NMR and mass spectroscopic data. These compounds were evaluated for their antibacterial activity against ten different gram positive and gram negative bacterial strains. The cytotoxic activity was performed against human keratinocyte cell lines. Part two is related to the synthesis of some 3-(substituted phenyl)isocoumarins, 3- (substituted phenyl)isocoumarin-1-thiones, 3-(substituted phenyl)isoquinolones and some 1-aryl-7,8-dichloroisochromans. Chapter seven, after general introduction, describes the synthesis and biological activity of these compounds. The unsubstituted homophthalic acid was converted into anhydride by treatment with acetic anhydride. The latter was then converted into 3-(substituted phenyl)isocoumarins by reacting it with suitable acid chlorides. The isocoumarins were then converted into corresponding 3-(substituted phenyl)isoquinolones by treatment with formamide. The 3-(substituted phenyl) isocoumarin-1-thiones were synthesized from isocoumarins using Lawesson’s reagent under microwave irradiation. Microwave assisted synthesis of some (±)-1-aryl-7,8- dichloroisochromans was carried out by condensation of 2-(3,4-dimethoxyphenyl) ethanol with a variety of aromatic aldehydes via an acid catalyzed oxa-Pictet-Spengler reaction. All of these synthesized compounds were characterized by IR, 1H, 13C NMR and mass spectroscopic data. In vitro antibacterial activity of these compounds was determined against ten different Gram positive and Gram negative bacterial strains using agar well diffusion method. The comparative analysis of the antibacterial activity of the 3-(substituted phenyl)isocoumarins, 3-(substituted phenyl)isocoumarin-1-thiones and 3-(substituted phenyl)isoquinolones is described. Accordingly, the antibacterial activity increases when isocoumarins were converted into corresponding isocoumarin-1-thiones but decreases on conversion into corresponding isoquinolones.
دساں کی حساب، حساب دے وچ دکھ لکھیا پیا کتاب دے وچ اوسے نور دا مڈھ ظہور ہویا جیہڑا چمکدا اے آفتاب دے وچ برہوں ہجردے وچ میں گئی بھنی سیخاں ہوندیاں جیویں کباب دے وچ ہووے غلطی جے کوئی معاف کرنا خط لکھیا گیا شتاب دے وچ اکھیں تکدیاں تکدیاں رہ گئیاں نشہ کیہڑا سی اوس شراب دے وچ جنگاں واسطے پانی دے ہونئیاں نے پانی سُکدا پیا چناب دے وچ کسے کامل ولی دی کر محفل کی لبھنا ایں خانہ خراب دے وچ کیہڑے حیف حنیف دے وچ رُجّھوں ایہو کجھ ہئی عشق دے باب دے وچ
Prophet Muhammad (Peace be upon him) asked the Ummat to build a strong bond with Quran and Sunnah. However, it was not possible to hold these, till both were not maintained in their original form. The science of Hadith has a significant role in the preservation of this Islamic Intellectual Heritage. It became possible because of the tremendous efforts of the Muslim Scholars who spent their entire lives in learning and spreading the Islamic knowledge. Imam Muslim bin Hajjaj al Qushairi 578 AD is one of the most enthusiastic, popular, and authentic personalities in the field of science of Hadith and among the bibliography of the narrators of Hadiths. His compilation As-Sahih Al-Jamey has a major contribution in preservation of Hadith. It is considered as the second most authentic book after The Quran. The paper discusses in details about the life of this intellectual personal, his journeys, his teachers, his students, his status, and his other research works.
Commitment to change is considered to be one of most important factors for the successful implementation of change initiatives (Herscovitch & Meyer, 2002). The purpose of the present research was to identify stressors and facilitators that could potentially have a bearing on employees’ commitment to change as well as factors that could mitigate the negative effects of these stressors on commitment to change. The relationship between commitment to change and related behavior is also a focus of the present thesis. A secondary purpose of the present research was also to validate the Herscovitch-Meyer (2002) three component (affective, continuance and normative) model of commitment to change in Pakistan. Survey data were collected from four large Pakistani public sector organizations where organizational restructuring had been initiated, in order to cross validate the research model across multiple samples. The rate of response varied, depending upon the level of support and access provided to the researcher by the respective organizations for data collection. The response rate was 43%, 21%, 28% and 60% for Organization 1, 2, 3, and 4 respectively. For the purpose of data analysis, exploratory and confirmatory factor analysis techniques were employed for validation of the Herscovitch-Meyer (2002) three component model of commitment to change. For testing hypotheses relating to the effect of stressors and facilitators on commitment to change, and for studying the effect of commitment to change dimensions on change related behavior, hierarchical multiple regression technique was used. Moderated multiple regression was used to test the effect of moderators on the relationship between stressors and commitment to change. iHierarchical multiple regression technique was also used to determine the relationship between commitment to change and change related behavior. The results provided support for the three component model despite some issues with the normative commitment to change scale. Job insecurity and role stressors were seen to be potent stressors having a negative relationship with affective and normative commitment to change and a positive relationship with continuance commitment to change. As expected, change related communication, employability and trust found support as facilitators of affective and normative commitment to change while their relationship with continuance commitment to change was observed to be negative. These facilitators were also seen to play a moderating role-albeit with limited support in present samples- in attenuating the negative relationship between stressors and affective/normative commitment to change and the positive relationship between stressors and continuance commitment to change. The present study is important for commitment research as it is an effort towards the identification of factors which may have a bearing upon the employees’ attitude towards commitment to change. For managers, the present study has important implications in terms of creating an organizational climate which minimizes stress and uncertainties. This positive environment can be made possible by ensuring an exchange of communication between decision makers and employees, provision of opportunities for employee development and allowing trust to develop between employer and employees which will have a positive impact on employee commitment to change. The results of the present study provide support for the generalizability of the Herscovitch-Meyer (2002) three component model of commitment to change in Pakistan. iiThere were however some issues concerning the reliability of normative commitment to change items due to which the analyses were performed after the removal of two items. Future research may be conducted on the construct employing cultural based items more suited to the Pakistani context. Future research may also explore the antecedents and consequences of commitment to change, taking stock of the limitations of the present study.