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Home > Synthesis, Structure Elucidation & Biological Evaluation of Molecules from Piperine Alkaloid

Synthesis, Structure Elucidation & Biological Evaluation of Molecules from Piperine Alkaloid

Thesis Info

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Author

Yasir, Ammar

Program

PhD

Institute

Government College University

City

Lahore

Province

Punjab

Country

Pakistan

Thesis Completing Year

2018

Thesis Completion Status

Completed

Subject

Chemistry

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/11008/1/AMMAR%20YASIR.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676727529532

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Piper nigrum is a medicinal plant and commonly used as household spice, having piperine alkaloid as major and active ingredient. Piperine is an antibacterial compound and its multiple uses have already been established in literature, therefore it is widely used in folk. There are many other potent antibiotics available in the market that contain substituited-1,3,4-oxadiazole heterocyclic ring structures. The high resistivity of microorganisms towards the prevailing drugs motivated us to synthesize new bioactive molecules by combining the piperine backbone to biological active oxadiazole system. It was assumed that 2,5 – disubstituited-1,3,4- oxadiazole heterocyclic ring may act as potent biological active molecules that boost the pharmacological activities to the new limits. The presented research work comprises the synthesis of some novel multifunctional derivatives followed by structural characterization & biological evaluation. Piperine alkaloid is extracted in lab using soxhlet apparatus, purified, further derivatized and characterized. Piperine, by basic hydrolysis, is converted to piperic acid, which on esterification changed into ethyl piperate and upon reaction with hydrazine lead to piperine hydrazide molecule, which acts as backbone for further derivatization. Piperine hydrazide in three different routes changed to 1-oxadaizole moiety by reacting with CS2 in aprotic solvents, 2- Imine functionality bearing molecules by reacting with various aldehydes, 3-sulphonamide functionalities by reacting with various aryl sulphonyl chlorides. Oxadiazoles further converted to oxatriazole by reacting with hydrazine. Overall we have synthesized 83 derivatives of piperine, with oxadiazole, oxatriazole, amide, imine and sulphonamide functionalities. The compounds presented in this work were synthesized according to available protocols in the literature and has been mentioned in seven schemes in detail (at the end of Chapter 1: Introduction). These synthesized compounds were purified through chromatographic techniques including column chromatography and preparative chromatography. Structures of all these were elucidated through IR, EIMS, 1H and 13C NMR spectroscopic techniques. As literature showed that various molecules containing these type of functionalities are biologically active and used for the treatment of various diseases. This encouraged us to evaluate piperine derivatives to search for more biological active or potent molecules. We have evaluated antibacterial, antifungal, hemolytic and thrombolytic xxvi activities. Some selected molecules from these series were also evaluated for analgesic and anti-inflammatory potential. The antibacterial activity was studied against both gram positive (Bacillus subtilus) and gram negative (Escherichia coli) bacterial strains and also evaluated as antifungal activity against Aspergilus niger strain. We have also investigated their toxicity through hemolytic and thrombolytic activities using blood as a substrate. Analgesic and anti-inflammatory activities for selected compounds were performed using swiss albino mice, which showed very encouraging results. Out of seven prepared series, the series (6a-s) in wihich piperidine ring is replaced with oxadiazole moiety shows most significant results. Two of the derivatives (6b & 6h) from this series (6a-s) found more potent antibacterial activity when compared with diclophenac sodium standard. From same series 6l & 6p showed improved hemolytic activity while 6e & 6f exhibited better thrombolytic activity as compared to piperine.7a-p series have aryl derivatives of oxadiazole-amide functionalities and in this series 7b showed the maximum antimicrobial activity while 7l and 7e of this series exhibited better hemolytic and thrombolytic activities respectively. A minor change in carbon chain for the series 8a-p as compared to 7a-p display overall decrease in activities, however prominent antibacterial and antifungal activities were shown by 8a and 8d. Schiff base containing derivative, 10l showed prominent hemolytic activity among the other members of this series. Sulphonamide bearing derivatives 11a-e showed moderate thrombolytic and hemolytic activity but 11e exhibited maximum antibacterial & antifungal activities. Oxatraizole containing derivative 12b and 12f found to have better thrombolytic activity as well as good antimicrobial agents.Selective derivatives were analyzed against analgesic and anti-inflammatory activities. Addition to Schiff Base moiety to piperine (10h) showed maximum analgesic activity (tail + hot plate method) even higher than Diclofenac sodium standard, while simple oxadiazole (5) and alkyl substituted oxadiazole (6o) showed maximum anti-inflammatory activities.Overall it is concluded that introduction of new functionality to piperine alkaloid made the molecules potent than the parent in most of the cases.
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80. ‘Abasa/looked indifferently

80. ‘Abasa/looked indifferently

I/We begin by the Blessed Name of Allah

The Immensely Merciful to all, The Infinitely Compassionate to everyone.

80:01
a. He contracted his brows - looked indifferently - and turned his face,

80:02
a. when the blind person came to him.

80:03
a. And what made you think that he, being a believer, may ask you and seek to purify himself,

80:04
a. or you would have guided him and he would have heard words of guidance and thus guidance from you would have benefited him.

80:05
a. Now as for the one who showed through his attitude that he had no need of guidance because of his wealth and social status -

80:06
a. and you were attending to him with full attention,

80:07
a. though you will not be answerable if he would not purify himself from disbelief?

80:08
a. But for the blind one who came to you with full of eagerness to learn,

80:09
a. and he was in awe of Allah,

80:10
a. you did not attend to him - you ignored him.

80:11
a. No, do not be so!
b. Indeed, this is a Reminder -

714 Surah 80 * ‘Abasa

80:12
a. So whoever wills, let him pay attention to it - Reminder.

80:13
a. The Qur’an is inscribed in pages of great esteem,

80:14
a. exalted and perfectly purified of any falsehood,

80:15
a. borne by the hands of scriber - angel envoys -

Developing An Improved Heart Rate Monitor With Work-Out Training Android Application And Real Time Audio Coaching

TechnoHeart is a digital way of monitoring heart rate using a Heart Rate Monitor device and an android phone. Moreover, this is made more special through its work-out training which is designed to help users set and achieve their target heart rate and monitor at what training intensity they are during a strenuous exercise. The training is made more interactive as the application has its real-time audio coaching. The need for this application comes from three sources; First, some athletes, non-athletes and even doctors are still using the traditional way of getting the heart rate; Second, training intensity is not monitored and target heart rate is not achieved; Third, most mobile developments do not tailor the need of users who undergo work-out training. With the following needs, objectives were set; First, to connect an HRM (Heart Rate Monitoring) device to an android mobile device and display individual’s heart rate in digital form through mobile; Second, to create a work-out training program using the Karvonen Formula; Third, to enable users know one’s target heart rate by using a Karvonen calculator; Fourth, to notify users in real time with every sudden change and the needed action in order to keep an effective training exercise. The project is to explore this and other similar concepts to develop a design that optimally satisfies all of these objectives. The project addresses all of these objectives while meeting the constraints given. The project was deployed in three different sets of users: The University of Mindanao Athletes, The elderly users aging from 50-80 years old and the other users aging from 12-49 years old. The researchers recommend the use of TechnoHeart for athletes and non-athletes who are aiming for an effective cardiovascular training. And for the next researchers, they can focus on the compatibility of the said application to other mobile platforms like iOS, Blackberry, Windows and etc. And also, they may upload application in the internet such as in social networking sites or any features that would make this project more usable.

Cycle Discrepancy of Graphs

In this thesis a new graph invariant, cycle discrepancy, is introduced. The optimal bounds on the cycle discrepancy for class of three-regular graphs and class of 3-colorable graphs are found. If the class of three-regular graphs is further restricted to Halin graphs, the established bound on cycle discrepancy reduces linearly. Necessary and sufficient conditions are given for a graph to have maximum possible cycle discrepancy. Further, it is shown that computing cycle discrepancy of a graph is an NP-hard problem. Let G = (V,E) be an undirected simple graph on n vertices. The cycle discrepancy of G, denoted as cycdisc(G) is in general bounded as: 0 ≤ cycdisc(G) ≤ ⌈n 2 ⌉. If G is a three colorable graph then cycdisc(G) is tightly bounded by ⌊n 3 ⌋. For d > 3, such d-colorable graphs are presented that have maximum possible cycle discrepancy. If G is a cubic graph then there is a tight bound of n+2 6 on its cycle discrepancy. An O(n2) algorithm is also presented to label the vertices of G such that cycdisc(G) ≤ n+2 6 . If G is not only cubic but also a Halin graph then cycdisc(G) ≤ n 8 +O(log n) and this bound is tight apart from the additive O(log n) term. It is also established that if minimum-degree of G is 3n 4 then cycdisc(G) = ⌈n 2 ⌉. Further, for n > 6, if maximum-degree of G is Δ and Δ2 < n − 1, then cycdisc(G) < ⌈n 2 ⌉. A graph is also constructed with maximum-degree n 2 + 2, that has maximum possible cycle discrepancy. This thesis provides a ground for further investigation in this area.