scholarly journals Isolation and Structure Elucidation of Rebaudioside D2 from Bioconversion Reaction of Rebaudioside A to Rebaudioside D

2014 ◽  
Vol 9 (8) ◽  
pp. 1934578X1400900 ◽  
Author(s):  
Indra Prakash ◽  
Cynthia Bunders ◽  
Krishna P. Devkota ◽  
Romila D. Charan ◽  
Catherine Ramirez ◽  
...  
Keyword(s):  
Spectral Data ◽  
Structure Elucidation ◽  
Rebaudioside A ◽  
Mass Spectral Data ◽  
Complete Structure ◽  
Mass Spectral ◽  
Steviol Glycoside ◽  
Extensive Analysis ◽  
Rebaudioside D

We report the isolation and complete structure of an isomer of rebaudioside D, known as rebaudioside D2. This novel steviol glycoside was isolated from a bioconversion reaction of rebaudioside A to rebaudioside D. Rebaudioside D2 possesses a relatively rare 1→6 sugar linkage, which was discovered by extensive analysis of NMR (1H, 13C, COSY, HSQC-DEPT, HMBC, 1D TOCSY and NOESY) and mass spectral data.

scholarly journals A New Diterpene Glycoside: 15α-Hydroxy-Rebaudioside M Isolated from Stevia rebaudiana

2015 ◽  
Vol 10 (7) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Indra Prakash ◽  
Gil Ma ◽  
Cynthia Bunders ◽  
Krishna P. Devkota ◽  
Romila D. Charan ◽  
...  
Keyword(s):  
Spectral Data ◽  
Structure Elucidation ◽  
Stevia Rebaudiana ◽  
Hydroxyl Group ◽  
Mass Spectral Data ◽  
Complete Structure ◽  
Mass Spectral ◽  
Steviol Glycoside ◽  
Stevia Rebaudiana Bertoni

In a continued search for novel diterpenoid glycosides, we recently isolated and characterized a Rebaudioside M derivative with a hydroxyl group at position 15 in the central diterpene core from an extract of Stevia rebaudiana Bertoni. Here we report the complete structure elucidation of 15α-hydroxy-Rebaudioside M (2) on the basis of NMR (1H, 13C, COSY, HSQC-DEPT, HMBC, 1D TOCSY, NOESY) and mass spectral data. Steviol glycoside with a hydroxyl group at C-15 in the central diterpene core has not been previously reported.

scholarly journals New Diterpene Glycosides from Stevia rebaudiana Bertoni: Rebaudioside VIII and Rebaudioside IXd

2018 ◽  
Vol 13 (10) ◽  
pp. 1934578X1801301
Author(s):  
Gil Ma ◽  
Allison Bechman ◽  
Cynthia Bunders ◽  
Krishna P. Devkota ◽  
Romila D. Charan ◽  
...  
Keyword(s):  
Spectral Data ◽  
Stevia Rebaudiana ◽  
Steviol Glycosides ◽  
Mass Spectral Data ◽  
Complete Structure ◽  
Mass Spectral ◽  
Stevia Rebaudiana Bertoni ◽  
Rebaudioside D

With our interest of new diterpene glycosides with better taste profile than Rebaudioside M, we isolated and characterized two steviol glycosides with three additional glucose attached at the C-13 of Rebaudioside M or Rebaudioside D from an extract of Stevia rebaudiana Bertoni. Here we report the complete structure elucidations of diterpene glycosides on the basis of NMR experiments (1H, 13C, COSY, HSQC-DEPT, HMBC, 1D TOCSY, NOESY) and mass spectral data. Steviol glycosides that possess eight or nine glucose units are rarely reported in literature and could have an impact on the natural sweetener catalog.

scholarly journals Complete Structure Elucidation of New Steviol Glycosides Possessing 9 Glucose Units Isolated from Stevia rebaudiana

2017 ◽  
Vol 12 (10) ◽  
pp. 1934578X1701201 ◽  
Author(s):  
Indra Prakash ◽  
Sangphyo Hong ◽  
Gil Ma ◽  
Cynthia Bunders ◽  
Krishna P. Devkota ◽  
...  
Keyword(s):  
Spectral Data ◽  
Structure Elucidation ◽  
Stevia Rebaudiana ◽  
Steviol Glycosides ◽  
Mass Spectral Data ◽  
Complete Structure ◽  
Mass Spectral ◽  
Stevia Rebaudiana Bertoni ◽  
Glycoside Linkage

In our continued effort to discover new diterpene glycoside sweeteners from Stevia rebaudiana Bertoni with a better taste profile than that of rebaudioside M, we have isolated three novel steviol glycosides with 9 glucose units, 3 at the C-13 site of the aglycone backbone and 6 at the C-19 site. Compounds 2-4 contain an additional tri-glucosyl unit attached to the C-19 glycoside region of rebaudioside M. For compounds 2 and 3 this unit is attached via the relatively rare 1→6 α-glycoside linkage. For compound 4 this additional unit is attached via the uncommon 1→3 α-glycoside linkage. In this paper, we describe the complete structure elucidation of novel diterpene glycosides with 9 sugar moieties by NMR (1H, 13C, COSY, HSQC-DEPT, HMBC, 1D TOCSY, NOESY) and mass spectral data.

scholarly journals Synthesis, Spectral and Anthelmintic Activity Studies on Some Novel Imidazole Derivatives

2008 ◽  
Vol 5 (s2) ◽  
pp. 1133-1143 ◽  
Author(s):  
Rajiv Dahiya ◽  
Anil Kumar
Keyword(s):  
Amino Acids ◽  
Spectral Data ◽  
Elemental Analysis ◽  
Structure Elucidation ◽  
Anthelmintic Activity ◽  
Coupling Agents ◽  
Mass Spectral Data ◽  
Mass Spectral ◽  
H Nmr ◽  
C Nmr

Present study describes the synthesis of a novel series of 3,5-diiodo-4-(5-nitro-1H-2-imidazolyl)benzoyl amino acids and di/tri/tetrapeptides using diisopropylcarbodiimide/dicyclohexylcarbodiimide (DIPC/DCC) as coupling agents andN-methylmorpholine/triethylamine (NMM/TEA) as bases. Structure elucidation of all the newly synthesized compounds was done by elemental analysis and IR,1H NMR,13C NMR and mass spectral data. Synthesized imidazolopeptides were screened for their anthelmintic activity and found to possess moderate to good bioactivity against earthwormsMegascoplex konkanensis, Pontoscotex corethruses and Eudrilus eugenieawhen compared to reference drugs - albendazole and mebendazole at dose level of 2 mg mL−1.

scholarly journals Novel Ent-Kaurene Glycosides with Eight Glycosyl Units from Stevia rebaudiana

2018 ◽  
Vol 13 (2) ◽  
pp. 1934578X1801300
Author(s):  
Indra Prakash ◽  
Bin Wang ◽  
Gil Ma ◽  
George Harrigan ◽  
Steven F. Sukits ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
Structure Elucidation ◽  
Stevia Rebaudiana ◽  
2D Nmr ◽  
Steviol Glycosides ◽  
Mass Spectral Data ◽  
Glycosylation Pattern ◽  
2D Nmr Spectroscopy ◽  
Complete Structure ◽  
Mass Spectral

Several steviol glycosides from Stevia rebaudiana are associated with extremely potent sweetness and are sought-after as low-calorie alternatives to sucrose. With the exception of a few nine sugar glycosides, steviol glycosides described in the scientific literatures contain less than a total of seven glycosyl units. We present here two new steviol glycosides, rebaudioside VIIIa (1) and VIIIb (2) containing eight sugar units isolated from S. rebaudiana Bertoni. The complete structure elucidation of these ent -kaurene diterpene glycosides with eight sugar units was completed using 1D- and 2D-NMR spectroscopy experiments (1H, 13C, 1H-1H COSY, 1H-13C HSQC-DEPT, 1H-13C HMBC, 1D TOCSY, and 1H-1H ROESY) and mass spectral data. Both compounds have four glycosyl units each attached to the C-13 and C-19 positions of aglycone core but vary in the glycosylation pattern and number of glucose and rhamnose units. This report therefore expands the catalog of highly glycosylated components from S. rebaudiana.

1-O-(13-Methyl-1-Z-tetradecenyl)-2-O-(13-methyItetradecanoyl)- glycero-3-phospho-ethanolamin, ein Plasmalogen aus Myxococcus stipitatus/ 1-O-(13-Methyl-1-Z-tetradecenyl)-2-O-(13-methyltetradecanoyl)-glycero-3-phosphoethanolamine, a Plasmalogen from Myxococcus stipitatus

1987 ◽  
Vol 42 (8) ◽  
pp. 1017-1020 ◽  
Author(s):  
J. Stein ◽  
H. Budzikiewicz
Keyword(s):  
Spectral Data ◽  
Structure Elucidation ◽  
Mass Spectral Data ◽  
Mass Spectral ◽  
C Nmr

AbstractThe structure of 1-O-(13-methyl-1-Z-tetradecenyl)-2-O-(13-m ethyltetradecanoyl)-glycero- 3-phospho-ethanolamine isolated from Myxococcus stipitatus has been elucidated. 1H and 13C NMR as well as mass spectral data have been accumulated which allow a ready identification and structure elucidation of compounds of this type.

scholarly journals Green Synthetic Protocol for (E)-1-Aryl-3-(2-morpholinoquinolin- 3-yl)prop-2-en-1-ones and Their Antimicrobial Activity

2019 ◽  
Vol 31 (9) ◽  
pp. 1895-1898
Author(s):  
Relangi Siva Subrahmanyam ◽  
Venkateswara Rao Anna
Keyword(s):  
Antimicrobial Activity ◽  
Spectral Data ◽  
1H Nmr ◽  
13C Nmr ◽  
Mass Spectral Data ◽  
In Vitro Antimicrobial Activity ◽  
Mass Spectral ◽  
Fungal Organisms

We report here an easy, efficient and green synthetic protocol for the (E)-1-aryl-3-(2-morpholinoquinolin-3-yl)prop-2-en-1-ones by the Claisen-Schmidt condensation of 2-morpholinoquinoline-3-carbaldehyde and different substituted acetophenones by using 1-butyl-3-methylimidazolium tetrafluoroborate (Bmim)BF4. The compounds were characterized by using 1H NMR, 13C NMR and mass spectral data and screened there in vitro antimicrobial activity against different bacterial and fungal organisms.

scholarly journals N-(2-(1H-Indol-3-yl)ethyl)-2-(6-methoxynaphthalen-2-yl)propanamide

Molbank ◽  
10.3390/m1187 ◽  
2021 ◽  
Vol 2021 (1) ◽  
pp. M1187
Author(s):  
Stanimir Manolov ◽  
Iliyan Ivanov ◽  
Dimitar Bojilov
Keyword(s):  
Spectral Data ◽  
13C Nmr ◽  
Title Compound ◽  
High Yield ◽  
Mass Spectral Data ◽  
Mass Spectral

The title compound was obtained in high yield in the reaction between tryptamine and naproxen. The newly synthesized naproxen derivative was fully analyzed and characterized via 1H, 13C-NMR, UV, IR, and mass spectral data.

scholarly journals (1R,4S,5S)-5-((3-Hydroxypropyl)amino)-4-((1-Methyl-1H-tetrazol-5-yl)thio)Cyclopent-2-en-1-ol

Molbank ◽  
10.3390/m1199 ◽  
2021 ◽  
Vol 2021 (2) ◽  
pp. M1199
Author(s):  
Milene A. G. Fortunato ◽  
Filipa Siopa ◽  
Carlos A. M. Afonso
Keyword(s):  
Spectral Data ◽  
13C Nmr ◽  
Ring Opening ◽  
Environmentally Friendly ◽  
Mass Spectral Data ◽  
Mass Spectral ◽  
Excellent Yield ◽  
Ring Opening Reaction ◽  
Nucleophilic Ring Opening

Using environmentally friendly conditions, the nucleophilic ring-opening reaction of 6-azabicyclo[3.1.0]hex-3-en-2-ol with 1-methyl-1H-tetrazole-5-thiol provided a novel thiol-incorporated aminocyclopentitol, (1R,4S,5S)-5-((3-hydroxypropyl)amino)-4-((1-methyl-1H-tetrazol-5-yl)thio)cyclopent-2-en-1-ol, in excellent yield (95%). The newly synthesized compound was analyzed and characterized via 1H, 13C-NMR, HSQC, and mass spectral data.

Sign in / Sign up

Export Citation Format

Share Document