Dr. Subhadip De

Accomplished researcher with extensive experience at Syngene International Limited, specializing in experimental design and data analysis. Proven track record in scientific writing and grant writing, driving innovative projects in organic chemistry. Adept at leveraging Computer-Aided Drug Design (CADD) to enhance research outcomes and foster collaboration in multidisciplinary teams.

Publications (in peer-reviewed scientific journals)

1. Subhadip De, Breanna Tomiczek, Yinuo Yang, Kenneth Ko, Ion Ghiviriga, Adrian Roitberg*, Alexander J. Grenning * "Diastereoselective Indole-Dearomative Cope Rearrangements by Compounding Minor Driving Forces” Org. Lett. 2022, 24, 3726-3730.

2.  Subhadip De, Junli Yin, and Dawei Ma* "Copper-Catalyzed Coupling Reaction of (Hetero)Aryl Chlorides and Amides"  Org. Lett. 2017, 19, 4864-4867.

3.  Subhadip De, Mrinal Kanti Das, Subhajit Bhunia, and Alakesh Bisai* "Unified Approach to the Spiro(pyrrolidinyl-oxindole) and Hexahydropyrrolo[2,3-b]indole Alkaloids: Total Syntheses of Pseudophrynamines 270 and 272A", Org. Lett. 2015, 17, 5922–5925.

4.  Subhadip De, Santanu Ghosh, Subhajit Bhunia, Javeed Ahmad Sheikh, and Alakesh Bisai* "Intramolecular Direct Dehydrohalide Coupling Promoted by KOtBu: Total Synthesis of Amaryllidaceae Alkaloids Anhydrolycorinone and Oxoassoanine", Org. Lett., 2012, 14, 4466-4469).

5.  Subhadip De, Mrinal Kanti Das, Avishek Roy, and Alakesh Bisai* "Synthesis of 2-Oxindoles Sharing Vicinal All-carbon Quaternary Stereocenters via Organocatalytic Aldol Reaction" J. Org. Chem., 2016, 81, 12258–12274.

6.  Subhadip De, Sourabh Mishra, Badrinath N. Kakde, Dhananjay Dey, and Alakesh Bisai* "Expeditious Approach to Pyrrolophenanthridones, Phenanthridines, and Benzo[c]phenanthridines via organocatalytic Direct Biaryl-Coupling Promoted by Potassium tert-Butoxide" J. Org. Chem. 2013, 78, 7823–7844.

7.  Mrinal Kanti Das,‡ Subhadip De,‡ Shubhashish, and Alakesh Bisai* "Concise total syntheses of (±)-mesembrane and (±)-crinane", Org. Biomol. Chem. 2015, 13, 3585-3588. [‡Both authors contributed equally].

8.  Subhadip De, Lakshmana K. Kinthada, and Alakesh Bisai* "Base-Promoted Michael Reaction Concomitant with Alkylation of Cyclic-1,3- diones; An Efficient Approach to 2-Substituted Vinylogous Esters", Synlett 2012, 23, 2785-2788.

9.   Subhadip De, Saikat Chaudhuri, Sourabh Mishra, Himanshu Mamtani, and Alakesh Bisai* "Pd-Catalyzed direct arylation approach to the 6H-dibenzo[c,h]chromenes : Total synthesis of arnottin I", J. Indian Chem. Soc.2013, 90, 1871-1884.

10.  Subhajit Bhunia, Subhadip De and Dawei Ma* "Room Temperature Cu-Catalyzed N-Arylation of Oxazolidinones and Amides with (Hetero)Aryl Iodides” Org. Lett. 2022, 24, 1253-1257.

11.  Santanu Ghosh, Subhadip De, Badrinath N. Kakde, Subhajit Bhunia, Amit Adhikary, and Alakesh Bisai* "Intramolecular Dehydrogenative Coupling of sp2 C-H and sp3 C-H Bonds: An Expeditious Route to 2-Oxindoles", Org. Lett. 2012, 14, 5864-5867.

12.   Badrinath N. Kakde, Subhadip De, Dhananjay Dey and Alakesh Bisai* "Metal Triflate-Catalyzed Cyclization of Arylvinylcarbinols: Formal Synthesis of (±)-Dichroanone and (±)-Taiwaniaquinone H", RSC Adv. 2013, 3, 8176–8179.

Mrinal Kanti Das, Subhadip De, Shubhashish, and Alakesh Bisai* "Concise Total Syntheses of (±)-joubertiamine, (±)-Omethyljoubertiamine, (±)-3'-methoxy-4'-O-methyljoubertiamine, (±)-mesembrane and (±)-crinane", Synthesis

2016, 48, 2093-2104.

14.   Govind Goroba Pawar, Haibo Wu, Subhadip De, and Dawei Ma* "Copper(I) Oxide/N,N’-Bis[(2-furyl)methyl]oxalamide-Catalyzed Coupling of (Hetero)aryl Halides and Nitrogen Heterocycles at Low Catalytic Loading" Adv. Synth. Catal. 2017, 359, 1631-1636.

15.   Lakshmana K. Kinthada, Santanu Ghosh, Subhadip De, Dhananjay Dey and Alakesh Bisai* "Acid-Catalyzed Reactions of 3-Hydroxy-2-oxindoles with Electron-rich Substrates: Synthesis of 2-Oxindoles with All-Carbon Quaternary Centers", Org. Biomol. Chem. 2013, 11, 6984-6993.

16.   Subhajit Bhunia, Saikat Chaudhuri, Subhadip De, K. Naresh Babu, and Alakesh Bisai* "An expeditious route to the synthesis of the enantioenriched tetracyclic core of ergot alkaloids via an organocatalytic aldol reaction", Org. Biomol. Chem., 2018, 16, 2427-2437.

17.   Santanu Ghosh, Subhajit Bhunia, Badrinath N. Kakde, Subhadip De, and Alakesh Bisai* "Enantioselective construction of vicinal all-carbon quaternary centers via catalytic double asymmetric decarboxylative allylation", Chem. Commun. 2014, 50, 2434-2437.

18.  Arindam Maity, Avishek Roy, Mrinal Kanti Das, Subhadip De, Malay Naskar and Alakesh Bisai* “Oxidative Cyanation of 2-Oxindoles: Formal Total Synthesis of (±)-Gliocladin C”, Org. Biomol. Chem., 2020, 18, 1679-1684.

Publication (in peer-reviewed conference)

19.   Sourabh Mishra, Subhadip De, Badrinath N. Kakde, Dhananjay Dey and Alakesh Bisai* "Expeditious approach to the Amaryllidaceae alkaloids, crinasiadine and its analogues, via a palladium-catalyzed intramolecular direct C-H arylation", IJC A, 2013, 52A, 1093-1102. [Special Issue INDO-GERMAN Conference on Complex Chemical Systems].

International Patent (Granted):

20.   Robert M Williams, Sivanagireddy Koti, Subhadip De, Anil M Shelke, Ryan E Cerbone, Nobuyoshi Yosuda “Synthesis of Structural Analogs of Largazole and Associated Compounds”]; Patent No.: US 12,227,522 B2; Publication date: Feb, 18, 2025.

Total no. of manuscripts reviewed. = 16

• March, 2012: Advances in Pharmaceutical Research and Chemistry – Poster Presentation: NITTTR Bhopal, Shamla Hills, Bhopal, Madhya Pradesh, INDIA
• Poster Title: "Approaches to the C(3a)-Quaternary Stereocenter Based Pyrroloindoline Alkaloids via Friedel-Craft's Alkylations".
• December, 2012: INDO-GERMAN Conference on "Complex Chemical Systems"– Participant: IISER Bhopal, Bhopal, Madhya Pradesh, INDIA.
• December, 2013: IX J-NOST Conference – Poster Presentation IISER Bhopal, Bhopal, Madhya Pradesh, INDIA
• Poster Title: "Intramolecular Homolytic Aromatic Substitution (IHAS) Promoted by Potassium tert-Butoxide: Expeditious Approach to the Phenanthridines and Benzo[c]phenanthridines".
• August, 2014: INTeRaCTIONS: In-house Symposium – Oral Presentation IISER Bhopal, Bhopal, Madhya Pradesh, INDIA.
• Talk Title: "Intramolecular Homolytic Aromatic Substitution (IHAS) Promoted by KO'Bu: Total Synthesis of Amaryllidaceae Alkaloids".
• December, 2014: X J-NOST Conference – Poster Presentation Indian Institute of Technology, Madras, INDIA.
• Poster Title: "Intramolecular Homolytic Aromatic Substitution (IHAS) Promoted by KO'Bu: Applications in Total Synthesis of Alkaloids".
• September, 2015: INTeRaCTIONS: In-house Symposium – Participant IISER Bhopal, Bhopal, Madhya Pradesh, INDIA.
• October, 2016: "The 12th International Symposium on Organic Free Radicals" – Participant: SIOC, Shanghai, CHINA.
• May, 2021: "Synth-Posium by the Sea 2021" – Participant & Poster Judge: University of Florida, Florida, USA

• Ph.D. Experience: The thesis entitled "Total Syntheses of Benzo[c]phenanthridine and Pyrroloindoline Alkaloids via Transition Metal-Free C-C Bond-Forming Reactions" was divided into two parts viz. Part A and Part B. A concise summary of research projects during PhD is described below. Part A entitled "Total Synthesis of Benzo[c]phenanthridine Alkaloids via Intramolecular Homolytic Aromatic Substitution (IHAS)" deals with the development of KO'Bu-promoted Intramolecular Homolytic Aromatic Substitution (IHAS) with the aid of a catalytic amount of bidentate organic ligands as shown in Scheme 1. Interestingly, it was observed that the method also works just in the presence of 3 eq. of KO'Bu, without the use of organic molecule as ligand (conditions C). Utilizing the mentioned methodology a concise and straightforward total syntheses of a number of Amaryllidaceae alkaloids, such as oxoassanine, anhydrolycorine, 5,6-dihydrobicolorine, and dihydrobenzo[c]phenanthridines alkaloids such as dihydroavicine, dihydronitidine and dihydrochelerythidine was completed. Interestingly, further extending this method, a concise total syntheses of benzo[c]phenanthridine alkaloids such as nornitidine, and norchelerythrine was also achieved. [Org. Lett. 2012, 14, 4466 & J. Org. Chem. 2013, 78, 7823]. Part B of the thesis entitled "Synthetic Approaches to the Dimeric Pyrroloindoline Alkaloids via Organocatalytic Aldol Reaction" deals with the development of organocatalytic aldol reactions with paraformaldehyde as C1 unit catalyzed by thio-urea (TU) catalyzed enantioselective aldol reaction. This methodology was implemented for synthetic approaches to dimeric pyrroloindoline alkaloids sharing all-carbon quaternary stereocenters. A wide variety of thio-urea based ligands have been synthesized and utilized in deracemization of 3-substituted 2-oxindoles by reaction with paraformaldehyde as C1 unit to afford a numbers of enantioenriched 2-oxindole derivatives. This process follows a dynamic kinetic asymmetric transformation (DYKAT), which essentially follows the Curtin- Hammett principle. The above strategy was utilized for total syntheses of spiro-pyrroloindoline alkaloids, (+)-coerulescine and (+)-horsfiline, pyrroloindoline alkaloids, (–)-deoxyseroline and (–) esermethole. Further, first enantioselective syntheses of prenylated pyrroloindole alkaloids, (–)- pseudophrynamines 272A and 270 were also achieved using the same strategy (scheme 2). On further exploration of this strategy, advanced potential intermediates for total syntheses of (+)-chimonanthine and meso-chimonanthine were synthesized (scheme 3). [Org. Lett. 2015, 17, 5922 & J. Org. Chem. 2016, 81, 12258].
• Postdoctoral Experience from Shanghai Institute of Organic Chemistry: N,N'-Bis-(thiophen-2-ylmethyl)oxalamide (BTMO) is an efficient ligand for Cu-catalyzed Goldberg-amidation coupling with inferior reactive (hetero)aryl chlorides (Scheme 4). The humbled nucleophilicity of amides (electron-withdrawing carbonyl groups) as compared to amines make them challenging partners in metal-catalyzed cross-coupling reactions. Utilizing this catalytic system, the synthesis of a wide variety of N-arylated amides, lactams, and oxazolidinones was carried out. [Org. Lett. 2017, 19, 4864 & Adv. Synth. Catal. 2017, 359, 1631].
• Postdoctoral Experience from Colorado State University: Histone deacetylase (HDAC) inhibitors are targeted therapies for the treatment of cancer. Numerous small-molecule HDAC inhibitors have been identified in nature or developed in medicinal chemistry. Several naturally occurring and synthetic HDAC inhibitors are reported to date. We are assuming that CT 101 might be one of them. Hence, work has focused on the synthesis of base fragment (15) and CT 101 (14) through a novel and effective enantioenriched route.
• Postdoctoral Experience from University of Florida: Reported herein is the discovery of a diastereoselective indole-dearomative Cope rearrangement. A suite of minor driving forces, including substrate destabilization through steric congestion and product stabilization via conjugation events and an aromatic p-p
• Stack, are what promote this otherwise unfavorable dearomatization reaction. The key substrates are rapidly assembled from alkylidenemalononitriles and indole-phenylmethanol derivatives resulting in many successful examples. The products are structurally complex bearing vicinal stereocenters generated by the dearomative Cope rearrangement. They also contain a variety of functional groups for interconversion. On this line, also described herein are proof-of-concept strategies for achieving enantioselectivity and conversion of the dearomative products to valuable and functionalized small drug-like molecules (Org. Lett. 2022, 24, 3726-3730).

• 2025 ACS Publications Peer Reviewer
• Certified Peer Reviewer Course - Elsevier

• Spot Award, Syngene International Ltd.: In recognition of significant contribution towards successful deliverables and client satisfaction that resulted in business expansion (July 5, 2022).
  
• Business Achievement Award, Syngene International Ltd.: In recognition to team member’s deduction, commitment, and outstanding contributions towards the problem solving and successful delivery of the project for “Roivant Discovery” (August 10, 2022).
• Spot Award, Syngene International Ltd.: Excellence in project delivery on time (August 24, 2023).
  
• International Postdoctoral Fellowship: CAS President's International Fellowship Initiative (PIFI) for Postdoctoral Researchers, China (August, 2016 – July, 2018).
  

• "Synth-Posium by the Sea 2021" – Poster Judge: University of Florida, Florida, USA