Subramanian Arumugam

Design, Network Analysis and In Silico Modeling of Biologically Significant 4-(substituted benzyl)-2-Amino-6-HydroxyPyrimidine-5-Carboxamide Nanoparticles

The synthesized 4-(4-hydroxy benzyl)-2-amino-6-hydroxy pyrimidine-5-carboxamide was chosen to perform in silico modeling with identified drug target AGT, TNF, F2 and BCL2L1. The identified human proteins are vital in the pain management and also an important target for the study of wound healing activity. The enzymes were identified by using BioGRID, string database and network analysis through Cytoscape software. The wound healing activity was evaluated by excision wound model. The observed results revealed that, the pyrimidine nanoparticles showed significant wound healing activity compared to standard and synthesized compound. The detailed synthesis of nanoparticles formulation spectral analysis and pharmacological screening datas were reported. The revealed reports of synthesized analogues and formulated nanoparticles will generate a very good impact to the chemists and research scholars for further investigations in wound healing and pain management.

Graph Theoretical Analysis, Insilico Modeling, Design, and Synthesis of Compounds Containing Benzimidazole Skeleton as Anti-depressant Agents

In this study, drug target was identified using KEGG database and network analysis through Cytoscape software. Designed series of novel benzimidazoles were taken along with reference standard Flibanserin for insilico modeling. The novel 4‐(1H‐benzo[d]imidazol‐2‐yl)‐N‐(substituted phenyl)‐4‐oxobutanamide (3a–j) analogs were synthesized and evaluated for their antidepressant activity. Reaction of 4‐(1H‐benzo[d]imidazol‐2‐yl)‐4‐oxobutanoic acid (1) with 4‐(1H‐benzo [d] imidazol‐2‐yl)‐4‐oxobutanoyl chloride (2) furnished novel 4‐(1H‐benzo [d] imidazol‐2‐yl)‐N‐(substituted phenyl)‐4‐oxobutanamide (3a–j). All the newly synthesized compounds were characterized by IR, 1H‐NMR, and mass spectral analysis. The antidepressant activities of synthesized derivatives were compared with standard drug clomipramine at a dose level of 20 mg/kg. Among the derivatives tested, most of the compounds were found to have potent activity against depression. The high level of activity was shown by the compounds 3d, 3e, 3i, and it significantly reduced the duration of immobility time at the dose level of 50 mg/kg.

Key-Based Steganographic Textual Secret Sharing for Confidential Messaging

Many email communications remain unencrypted between end points, raising the need for additional encryption. This paper addresses the need by proposing a new cryptographic scheme, which first encrypts a message using key-based Shamir’s secret sharing (using multiple polynomial terms as opposed to only the constant) and discretely hides the shares throughout a cover image using a steganographic technique with number padding. It thus employs multi-layer security requiring the key, the original cover image and the decryption algorithm implementation to unlock the message. Its security is analysed, confirmed and an example given.

Visual Secret Sharing between Remote Participants

Visual cryptography and random grids are forms of visual secret sharing that encrypt a secret image into indecipherable shares. Decryption occurs by printing them onto transparencies and stacking, but this requires participants to be in the physical presence of each other, so this paper addresses the use of visual secret sharing between remote, incommunicado agents. To this end, a prototype application has been developed to form a subpixel matrix of a photographed share that is one half of a (2, 2) scheme. It is algorithmically “stacked” with its stored complement to decrypt the secret. The implemented algorithms are presented, as well as visual results for variations of three values of three photographic condition metrics. Although only a third of the total results proved positive, recommendations are given regarding photographic conditions to significantly improve accuracy. Furthermore, we suggest a number of applications of this technology.

Graph access structures with optimal pixel expansion three

Let G=(V,E) be a graph without isolated vertices. Let @C(G) denote the strong access structure whose basis is the edge set E and let m^@?(G) denote the optimal pixel expansion of a visual cryptography scheme for @C(G). In this paper we obtain a characterization of all connected graphs G with m^@?(G)=3.

On the use of secret sharing as a secure multi-use pad

Secret sharing (SS) is a cryptographic method proposed independently by Adi Shamir and George Blakley in 1979 to encode the keys of public-key cryptography by splitting them into maximally entropic shares that are distributed to participants, only revealing the secret when combined. Each new sharing instance, even of the same key, produces a different set of shares to distribute anew. This paper investigates SS as an independent cipher to secure confidential messages between a limited set of trusted participants by eliminating the need to redistribute shares. A participant’s master share is permanently fixed and unlimited temporary shares are created and combined with it to reveal new messages. Security is argued against specific and general attacks.

Design, docking analysis, identification, and synthesis of novel 3-(((substituted phenyl) amino)methyl)-2-methylquinazolin-4(3H)-one compounds to fight tuberculosis

In this study, a series of novel scaffold-based 3-(((substituted phenyl)amino)methyl)-2-methylquinazolin-4(3H)-one compounds, 3a-3r, was synthesized, characterized, and screened for its in vitro activity against the H37Ra strain of Mycobacterium tuberculosis. A number of analogs were found to have highly potent anti-tuberculosis activity. Compound 3m in particular had potent activity equal to that of the standard anti-tuberculosis drug rifampicin. New leads can be generated with the model developed in this study and this model will be optimized with the eventual goal of preparing new anti-tuberculosis agents.

AnimVSS: Frame-Based Visual Secret Sharing

Visual secret sharing is a cryptographic paradigm encrypting images into a number of individually random “shadow images”. When stacked, they reveal a contrast-reduced version of a secret image. In this paper, we consider random grid shadow images, which have gained increasing attention in recent years due to lack of pixel expansion inherent in Naor-Shamir visual cryptography. We propose a methodology to use such grids to encode series of frames comprising short animations, useful in situations when a mere static image is insufficient to convey a secret instruction. Although this method results in significant contrast degradation with longer animations, a method is devised to isolate the signal from the noise in a computational XOR-based decryption.