Objective: Free radicals like superoxide anion radical (O 2 .-), hydroxyl radical (HO.), alkyl radical (R.), alkoxy radical (RO.), peroxy radical (ROO.) and nitric oxide radical (NO.) often leads to oncogenic proliferation, damage deoxyribosyl backbone of DNA, accelerate oxidation of polydesaturated fatty acids, amino acids, and several other co-factors. Several carbazole moieties present in M. koenigii L. like murrayanine, mahanimbine, curryanine, kurryam have been reported to exhibit good anti-oxidant activity. The present research represents an effort to develop few novel hybridized derivatives of murrayanine (an active carbazole derivative) by reacting with various small ligands like urea, semi carbazide and thio semi carbazide with an intention to develop Schiff's base compounds with higher and potent anti-oxidant activity than its parent moiety (murrayanine). Methods: The study protocol involved DPPH radical scavenging assay and determining in vitro reducing activity of the semi-synthetic derivatives. Results: The study revealed that compound 5 exhibited highest anti-oxidant activity (IC 50 of 6.5 μM), followed by derivative 3 which displayed activity at IC 50 value of 7.3 μM, which was superior as compared to murrayanine 1 which scavenge the radical at IC 50 of 7.6 μM. However, two semi-synthetic compounds (2 and 4) exhibited lesser activity compared to murrayanine, IC 50 s of 7.8 and 8.1μM, respectively. The compounds exhibited absorbance in range 0.76-1.3. Highest absorbance of 1.079 was demonstrated by 5. Conclusion: This study can be concluded that these derivatives may have enough potential to be used as antioxidants and open new doors for research perspectives towards the development of novel radical scavenging moiety.

Murrayanine is the most highly explored molecule from Murraya koenigii L., known popularly as Indian curry plant (family Rutaceae) which demonstrates carminative, astringent, stomachic, purgative, febrifuge, anti-anemic, and anthelminthic. Thiadiazole is a scaffold of prime importance in medicinal chemistry. It has often been observed that thiadiazoles on hybridization with other heterocyclic scaffolds, demonstrates synergistic activity. Based on this fact, a hybrid of 1,3,4-thiadiazole was planned to fabricate with murrayanine and also to explore its synergistic potentials in a specific direction based on the available text information. The present study involved the synthesis of murrayanine-thiadiazole hybrids using a previously reported starting material (E)-2-((1-methoxy-9H-carbazol-3-yl)methylene)thiosemicarbazide and exploring the anti-inflammatory activity of the produced novel compounds. The compound 4c, containing 3-OCH 3 and 4-OH substituents displayed the highest edema reducing activity after 3 hrs. The enhanced activity may be due to the interaction of the hydrophilic moiety, via oxygen moiety with the active site of the inflammation causing elements like Cyclooxygenase (COX) and Lipoxygenase (LOX). We tried to establish a crystal clear structure-activity relationship, but due to mixed results, a true relationship cannot be predicted. Rather, an assumption was made based on the available interacting groups with the active sites of the chemical mediator. This research will definitely motivate global researchers in rationally designing of natural product-based heterocyclic hybrids which will have great perspective as therapeutic agents in future with reduced side-effects.

Based on the fact that three scaffolds; viz. murrayanine, Schiff's base, and hydantoin have been reported to exhibit potent anti-convulsant activity, therefore, all three of them were integrated to shape a hybrid molecule which is believed to demonstrate excellent anti-convulsant activity owing to the incorporation of scaffolds. The present research involved rational designing of anti-convulsant agents having murrayanine scaffold linked with hydantoin moiety via Schiff's base linkage with an objective that the analogs will demonstrate enhanced anti-convulsant activity than their parents and also show comparable activity with the standard drug. The anti-convulsant activity was screened at dose levels of 30, 100, and 300 mg/kg utilizing maximal electroshock-induced seizure (MES) threshold test where molecule (5) displayed the most potent activity at doses 30 mg/kg (0.5 hr) and 100 mg/kg (4 hr), respectively, with comparison to the standard drug, phenytoin. In contrast, the compound (8) compound exhibited activity at 100 mg/kg (0.5 hr) and 300 mg/ kg (4 hr), respectively in male Albino Swiss mice. The research revealed the prospective of murrayanine-Schiff's base-hydantoin derivatives as active anti-convulsant activity. The characterization data were found to be in full agreement with the structural aspects. The molecular docking study revealed the possible interaction of the ligands with the NaVAb voltage-gated sodium channel, thereby proving the possible mechanism of molecule action. This study will certainly promote researchers in the rational synthesis of hybrid molecules with pronounced anti-epileptic activity.

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Cancer is the second leading causes of mortality across the planet which has had affected millions. In spite of massive efforts in producing new molecules and chemotherapeutic approaches for managing cancer, it continued to be the global threat. Small hybrid molecules have gained popularity in chemotherapy due to their potential and smart characteristics in modulating biological targets. The present research attempts in developing few novel hybridized derivatives of murrayanine (an active carbazole derivative) by the semi-synthetic approach to form substituted thiazole linked murrayanine-Schiff's base derivatives. The protocol involved murrayanine 1 as the template material for constructing a hybridized Schiff's base intermediate 3, which further by Hantzch's cyclization was subsequently converted to various hybridized thiazoles analogs 5a-5f. The purity of the synthesized compounds was ascertained by sophisticated analytical techniques. The anti-cancer potential was screened against breast cancer cell lines; MCF-7 and MDA-MB-231 by Sulforhodamine B (SRB) assay. The compound 5b displayed most potent anti-proliferative activity with IC50 values of 23.41μM against MCF-7 cell line and 32.15μM against MDA-MB-231 cell line. It has been observed that analogs having electron withdrawing substituents exhibited pronounced anticancer activity. The docking study was performed by Autodock Vina where the results were found to be in full agreement with the cytotoxic study, depicting that the probable cytotoxic outcome by EGFR inhibitory mechanism. The study revealed the potential of novel hybridized derivatives as active anti-breast cancer candidates. The research will encourage (medicinal) chemists in rationally designing of semi-synthetic analogs of a heterocyclic prototype having pronounced anti-cancer activity. Keywords