Dr. Anil K. Tripathi

Bioorganic Chemistry Division
CSIR - Indian Institute of Integrative Medicine,Canal Road, Jammu – 180001
Email: aktripathi@iiim.ac.in, tripathitripathi@rediffmail.com

Positions Held  
Position Held Date Organization
Sr. Technical Officer-EI1 2014 - Present CSIR-IIIM
Sr. Technical Officer-E1 2009-2014 CSIR-IIIM
Sr. Technical Officer-C 2004-2009 CSIR-IIIM
Sr. Technical Officer-B 1999-2004 CSIR-IIIM
Sr. Technical Officer 1994-1999 CSIR-IIIM
Senior Technical Assistant 1989-1994 CSIR-IIIM
Junior Scientific Assistant 1983-1989 CSIR-IIIM
 
Honors and Awards  
Reviewer of research publications for international journals of repute e.g.
  • Current Organic Chemistry (Bentham Science Publishers)

  • Synthetic Communications (Taylor & Francis)

  • Indian Journal of Chemistry (NISCAIR)

  • Carbohydrate Polymers (Science Direct–Elsevier) etc.

   
Membership  
  • Life membership Indian Pharmaceutical Association

  • Life membership Indian Science Congress Association

 

Research Interest

  1. Chemistry and bioactivities of medicinal plants and generation of semi-synthetic libraries based on natural product scaffolds.

  2. Design and synthesis of bioactive lead molecules (drug development) in the area of anti hypertensive, anticancer, anti-inflammatory, insecticidal etc. based on natural products.

  3. Synthesis and kinetic resolution of important dugs/intermediates using chemo enzymatic methods.

  4. Development of green methodologies for the synthesis of benzopyran and related analogues as target potassium channel opener molecules using Microwave irradiation and sonication technology.

  5. Process development of important drug intermediates like Syringaldehyde, trimethoxy benzaldehyde, trimethoprim, ethyl vanillin, vanillin, methyl salisilate etc.

Diversity oriented synthesis of novel scaffolds embedded with privileged benzopyran motif
The reaction of 2-N-(Acetylanilino)-3-chloro-1,4-naphthoquinone with bifunctional aromatic amines afforded angular heterocycles  and thereafter reductive acetylation provided o-acyl and O,N-diacyl derivatives.

Synthesis of 2,2-Dimethyl-4-formyl-7-methoxy-(2H)-1-benzopyran with the reaction of Resorcinol Mesityl Oxide
Synthesis of 2,2-dimethyl-4-formyl-7-methoxy-(2H)-1-benzopyran has been achieved by a three step reaction sequence, wherein the key step has been the preparation of 7-hydroxy-2,2,4-trimethyl-(2H)-1-benzopyran by a novel condensation reaction between resorcinol and mesityl oxide in presence of polyphosphoric acid (PPA).
Bioefficacy of crude extracts of Aglaia species (Meliaceae) and some active fractions against lepidopteran larvae: Foliar and twig extracts of three species of Aglaia were screened for larval growth inhibiting and antifeedant effects against the polyphagous lepidopteran larvae of Spodoptera litura and Helicoverpa armigera. A. elaeagnoidea and A. odorata crude extracts were at par in their activity at an initial treatment lavel of 5 mg/g of dry diet weight, while A. roxburghiana was half as active as the other two species. Detailed investigation of A. elaeagnoidea species revealed the presence of complex limonoids fractions responsible for this activity. The nutritional analyses showed impaired diet consumption and dietary utilization at 200 ppm level of treatment when limonoid fractions Fr2J and Fr6K were provided orally to S. litura larvae, indicating centrally mediated anorexic effect. The isolation of the limonoid complex from A. elaeagnoidea should provide useful starting point for the development of a botanical anti-insect preparation.

Facile synthesis of various 4-carboxylicacid derivatives and their amide analogues of benzopyrans: A series of 4-carboxyalkyl amide derivatives of benzopyrans have been prepared (22 compounds) in 40-64% overall yields. In the proposed synthetic strategy, the key intermediate 4-methyl substituted chroman (3) was obtained by condensing substituted phenol and mesityl oxide in presence of PPA. The required carboxylic acid function has been introduced at C-4 in benzopyran ring through a novel route.

Synthesis and cytotoxicity of novel benzopyran derivatives: In-vitro cytotoxic activity of benzopyrones and benzopyran derivatives has been evaluated against a panel of several human cancer cell lines. Out of 16 compounds prepared and screened, four compounds have shown significant cytotoxicity against human breast, liver, colon and prostate cancer cell lines. Apoptosis rather than necrosis has been established as the mode of mechanism for the cytotoxicity of the studied molecules using Light Microscopic and Scanning Electron Microscopic techniques.

Syringaldehyde was prepared from para-Cresol : an alternative approach: Syringaldehyde was prepared from p-cresol via a three step reaction sequence in overall yield of 59-67%. The synthesis involved solvent free bromination followed by high pressure and temperature methoxilation and catalytical oxidation. The use of cupric chloride as a catalyst in two key steps i.e. methoxilation in aromatic ring and oxidation of aromatic methyl to aldehyde is not only novel but also renders the process more viable.

Microwave assisted facile and efficient synthesis of benzopyran: A convenient, fast and high yielding method for the preparation of 3,4-dihydrobenzopyrans has been achieved by the condensation of various acetophenones with different keto compounds in the presence of a base, assisted by Microwave activation under solvent free conditions with or without use of a solid support.

Synthesis and antimicrobial activity of 4-(2-substituted phenylthiazolidinyl)-benzopyran-4-one derivatives: A series of 7-(2-substituted phenylthiazolidinyl)-benzopyran-2-one derivatives have been synthesized by reaction of 7-amino-4-methyl-benzopyran-2-one (1) with an appropriate substituted aldehydes to obtain various Schiff bases (3a–k) which on treatment with thioglycolic acid afforded the title compounds (4a–j). Purity of the compounds has been confirmed by TLC. Structure of these compounds were established on the bases IR, 1H NMR, 13C NMR and Mass spectral data. Schiff bases and title compounds were evaluated for antibacterial and antifungal activities against various bacterial and fungal strains. The results showed that compounds 3d, 3f, 4d, 4f and 4i (100 mg/ml) exhibited good antibacterial and antifungal activity as that of standard antibiotics Ciprofloxacin and Griseofulvin.

Synthesis of Diindolylmethane derivatives: Series of diindolylmethane derivatives were synthesized by a green approach using a novel Fe-Al pillared clay catalyst and evaluated for antimicrobial activity. The new catalyst prepared has been characterized and its overall acidity optimized. Some of the compounds showed significant antimicrobial activity against S. aureus and resistant strains like MRSA and VRE, having MIC values within the range of 0.5-8 µg/ml. They were also found to be bactericidal in nature having MBC value < 4. One compound was found to be highly active among the series of synthesized DIM’s and also showed much higher potency than the control drug. A new class of DIM derivatives 4a-4d, prepared using benzopyran-4-one as substrate, also showed better activity than the standard drug.

 

Publications
  • Lambu, M.R.; Yousuf, S.; Tripathi, A.K.; Sharma, D.K.; Hussain, A.; Singh, B.; Mukherjee, D.Synthesis of C-spiro-glycoconjugates from sugar lactones via zinc mediated Barbier reaction.RSC Advances, (2014), 4, 11023-11028.

  • K. Sharma,D ; Tripathi,A. K.; Sharma,R; Chib,R. ; Rasool,R; Hussain,A; Singh,B.;Goswami,A.; Khan,I.A.; Mukherjee,D.; A new class of bactericidal agents against S. aureus, MRSA and VRE derived from bisindolylmethane. Medicinal Chemistry Research, (2013), 1-11.

  • Sharma,D. K.; Lambu,M. R.; Sidiq,T. ; Khajuria,A.; Tripathi,A. K.; Yousuf,S. K. ; Mukherjee,D . Ammonium chloride mediated synthesis of alkyl glycosides and evaluation of their immunomodulatory activity. RSC Advances, (2013) 3, 11450.

  • Kumar,D. A.; Tripathi ,A. K, Deshmukh ,V. K; Chaudhary ,S R: . A Review on Benzopyrans as Openers of the Mitochondrial ATP- Sensitive Potassium Channels, an Important Drug Target. Indian J of Phar Res. (2012),5(8) 4048-4055.

  • Sharma,D. K.; Rah,B.; Lambu,M.R.; Hussain,A. ; Yousuf,S. K.; Tripathi,A. K. ; Singh,B.; Jamwal,G.; Ahmed,Z.; Chanauria,N. ; Nargotra,A.; Goswami,A.; Mukherjee,D . Design and synthesis of novel N,N’-glycoside derivatives of 3,3’-diindolylmethanes as potential antiproliferative agents. Med. Chem. Commun.,(2012), 3, 1082.

  • Tripathi ,A. K;Mukherjee ,D.; Koul, S; Taneja, SC. Facile synthesis of various 4-carboxylicacid derivatives and their amide analogues of benzopyran. Indian J of Chem.(2012), 51B, April.

  • Tripathi ,A. K;Mukherjee, D.; Koul, S; Taneja ,SC; Agrawal .; Sharma ,P. R ; Saxena, A. K. (2011). Synthesis and cytotoxity of novel benzopyran derivatives. Indian J of Chem. 50B, Nov ( 2011), 1619-1629.

  • Tripathi ,A. K;Koul, S; Taneja ,SC . An Excellent Protocol for the Synthesis of Benzopyrans Using Basic Resin under MWI. CHem inform., vol 42, 11, March 15, (2011).

  • Tripathi ,A. K; Koul ,S; Taneja ,SC. An expeditious synthesis of syringaldehyde from para/cresol. CHem inform.,(2010). vol 41, 29, July 20.

  • Tripathi ,A. K; Koul ,S; Taneja ,SC . An Excellent Protocol for The Synthesis of Benzopyrans Using Basic Resin Under MWI. Indian J of Chem. (2010),49B, March

  • Tripathi ,A. K; Sama, JK; Taneja ,SC. An expeditious synthesis of syringaldehyde from para/cresol. Indian J of Chem. (2010),49B , 379-381.

  • Tripathi ,A.K;Koul, S; Taneja, SC . Microwave Assisted Facile Synthesis of Benzopyran. CHem inform.(2009), vol 40, 24, June 16.

  • Tripathi ,A. K; Mukherjee ,D.; Koul ,S; Taneja, SC. Facile synthesis of various 2-substituted-4-(2-pyridyl) benzopyran analogues as target potassium channel opener. Arkivoc, 2009 (xiii) 241-251.

  • Tripathi ,A. K; Koul, S ;and Taneja, SC . Microwave assisted facile and efficient synthesis of benzopyranm. Indian J of Chem. (2009),48B, 301-304.

  • Tripathi ,A. K; Khan, KR; Taneja ,SC . Reaction of Resorcinol with mesityl oxide: Synthesis of 2,2-Dimethyl-4-formyl-7-methoxy-2H-1-benzopyran. Synth Commun. (2003),33; 579.

  • Koul ,O; Shankar, JS; Mehta ,N; Taneja ,SC; Tripathi, A. K . Bioefficacy of crude extracts of Aglaia species (Meliaceae) and some active fractions against Lepidopteran larvae. J. Appl. Ent. (Germany),(1997), 121; 245.

  • Tripathi ,A.K; . Environment: Its protection. J. Pure and Appl. Soc. Sciences. 1(1).(1996)

  •  George ,V; Sharma, SD; Tripathi ,A. K; Abraham ,SP . Flavor components of some edible fungi from Kashmir. Pafai J. (1985),7(3); 27.

  • Agarwal, NL; Ghosh, S; Tripathi, A. K; Ata,l CK . Angular Heterocycles. A Convinient Synthesis of 6-N-(Acetylanilino)-5H-benzo[a]phenothiazin-5-one, 6-N-(Acetylanilino)-5H-benzo[a]phenoxazin-5-ones and their derivatives. J Heterocyclic Chem. (1984),21; 509.  

Patents

  • Tripathi ,A. K;Taneja, SC; Dhar, KL; Kapil, RS .  An improved process for the synthesis of syringaldehyde.(1995) (1461/Del/95).