Pharmaceutical Chemistry MCQ

1. The term Vicinal coupling describes-
(a) coupling between 1H nuclei in an alkane.
(b) coupling between 1H nuclei in an alkene.
(c) coupling between 1H nuclei attached to a djacent C atoms.
(d) coupling between 1H nuclei attached to the same C atom.

2. In the mass spectrum of the ethyl propanoate, a typical peak would be expected from a McLafferty ‘rearrangement’ at m/z of__
(a) 28
(b) 45
(c) 74
(d) 87

3. Which of the following peaks (m/z) does not appear in the mass spectrum of hexane?
(a) 36
(b) 43
(c) 57
(d) 86

4. Through which of the following injectors liquid samples can be injected into the column in GC?
(a) Gas tight syringe
(b) Micro-syringe
(c) Rotary sample valve
(d) Solid injection syringes

5. Which of the following is not true about ‘Hydraulic capacitance’ flow control system used in HPL?
(a) Maintains constant flow
(b) It is irrespective of solvent compressibility
(c) Can be useful only for less viscous liquids
(d) Smoothens high pressure pump pulsations

6. In _______the LC effluent passed through the heated probe and emerges as a jet of vapor and small droplets flowing into the desolvation chamber at low pressure.
(a) TSP Interface
(b) Continuous Fl ow FAB Interface
(c) DLI Interface
(d) Frit FAB Inter face

7. Which of the following best explains the antioxidant action of vitamin E?
(a) It is lipid soluble and can react with free radicals in the bloodstream resulting from nitric oxide formation by vascular epithelium
(b) It form s a stable radical that can be reduced back to active vitamin E by reaction with glutathione and glutathione peroxidase
(c) It form s a stable radical that can be reduced back to active vitamin E by reaction with vitamin C
(d) It is a radical, so when it reacts with another radical a non-radical product is formed

8. The 3 D’s (Dermatitis, Diarrhea, Dementia) are seen in the deficiency of:
(a) Thiamine
(b) Riboflavin
(c) Niacin
(d) Pyridoxine

9. IUPAC name of Thiamine is-
(a) 3-[3-[(2-methyl-4-aminopyrimidin-5-yl)methyl]-4-methyl-1,3-thiazol-3-ium-5-yl]ethyl chloride
(b) 2-[3-[(4-amino-2-methylpyrimidin-5-yl)methyl]-4-methyl-1,3-thiazol-3-ium-5-yl]ethyl chloride
(c) 3-[3-[(2-methyl-4-aminopyrimidin-5-yl)methyl]-4-methyl-1,3-thiazol-3-ium-5-yl]ethanol
(d) 2-[3-[(4-amino-2-methylpyrimidin-5-yl)methyl]-4-methyl-1,3-thiazol-3-ium-5-yl]ethanol

10. US Pharmacopeial G13 column comprises of___ phase?
(a) Cyanopropylpolysiloxane
(b) Dimethylpolysiloxane oil
(c) Sorbitol
(d) Neopen tylglycol succinate

11. Which amongst the following is not a hyphenated instrument?
(a) GC-MS
(b) LC-NMR
(c) GC-CE
(d) CE-MS

12. The number of stereocentres in Paclitaxel molecule are-
(a) Nine
(b) Ten
(c) Eleven
(d) Twelve

13. In Docetaxel, ____ is present on the phenylpropionate side chain instead of the benzamide in paclitaxel.
(a) tert-butyl carbamate ester
(b) n-decyl alkyl amido ester
(c) n-dodecyl alkyl amino ester
(d) iso-propyl carbamate ester

14. Etoposide is ?
(a) a-D-glucoside and furonaphthodioxole
(b) b-D-glucoside and furonaphthodioxole
(c) a-D-glucoside and furonaphthotrioxole
(d) b-D-glucoside and furonaphthotrioxole

15. Teniposide act by-
(a) inhibiting topoisomerase I
(b) inhibiting topoisomerase II
(c) intercalating into DNA
(d) binding strongly to DN A

16. The major mechanism by which plasmodia assumes resistance to chloroquine is-
(a) due to change in the structure of the active receptor
(b) on account of increased expression of p-glycoprotein
(c) increase in activity of DNA repair mechanism
(d) due to induction of inactivating enzyme

17. Primaquine intermediate 6-methoxy-8-nitroquinoline, is synthesized by Skraup reaction from-
(a) 4-methoxy-2-nitroaniline and glycerol in the presence of sulfuric acid
(b) 2-methoxy-4-nitroaniline and glycerol in the presence of sulfuric acid
(c) 6-methoxy-8-nitroaniline and glycerol in the presence of sulfuric acid
(d) 6-methoxy-4-nitroaniline and glycerol in the presence of sulfuric acid

18. Pyrimethamine, chemically is ?
(a) 5-(4-chlorophenyl)-4-ethylpyrimidine-2,4-diamine
(b) 4-(5-chlorophenyl)-5-ethylpyrimidine-1,3-diamine
(c) 5-(4-chlorophenyl)-6-ethylpyrimidine-2,4-diamine
(d) 3-(4-chlorophenyl)-5-ethylpyrimidine-2,4-diamine

19. β-lactam containing 2,3-dihydro-1H-pyrrole ring is named as-
(a) Penem
(b) Carbapenem
(c) Carbapenam
(d) Carbacephem

20. Monobenzyl ester of 3-Thienylmalonic acid is first converted to an acid chloride with thionyl chloride, and further reacted with 6-Aminopenicillanic acid (6-APA). Resulting intermediate on Hydrogenolysis with Pd/C gives-
(a) Cloxacillin
(b) Ticarcillin
(c) Carbenicillin
(d) Methicillin

21. In the conversion of Pyrrole to 3-chloropyridine, the reactive intermediate involved is a
(a) Nitrene
(b) Carbene
(c) Carbanion
(d) carbocation

22. An organic reaction that is used to convert an electron rich aromatic ring to an aryl aldehyde using DMF, an acid chloride, and aqueous work-up’ is known by which of the following named reaction?
(a) Shapiro reaction
(b) Doebner Miller reaction
(c) Beckmann rearrangement
(d) Vilsmeyer – Haack reaction

23. In this named reaction, phenol is converted to 2-hydroxy benzaldehyde and the reactive intermediate is dichlorocarbene ,
(a) Riemer Tiemann reaction
(b) Perkin reaction
(c) Mannich reaction
(d) Shapiro reaction

24. Which of the following reaction is an enantioselective chemical reaction to prepare 2,3-epoxyalcohols from primary and secondary allylic alcohols?
(a) Perkin reaction
(b) Sharpless epoxidation
(c) Mitsunobu reaction
(d) Smiles rearrangement

25. In this named reaction involving a dicarbonyl, an aldehyde, and ammonia, viewed as occurring in two stages, in the first stage, the dicarbonyl and ammonia condense to give a diimine with unusual orientation of N-H groups:
(a) Knorr’s pyrazole synthesis
(b) Debus-Radziszewski imidazole synthesis
(c) Pinner pyrimidine synthesis
(d) Combe’s quinoline synthesis

26. In which of the following drugs, the two isomers (R & S) compete with each other to bind the enzyme binding site resulting in the inhibition of the metabolism of the other isomer?
(a) Warfarin
(b) Propaphenon
(c) Propranalol
(d) Felodipine

27. Which of the following exhibits optical activity?
(a) Propan-2-ol
(b) 2-chlorobutane
(c) 1-chlorobutane
(d) Butan-2-one

28. Which of the following antiviral drugs is an adenosine analog that inhibits DNA polymerase
(a) Vidarabine
(b) Zidovudine
(c) Lamivudine
(d) Ritonavir

29. Which of the following drugs was first synthesized by the reaction of 4-amino-5-nitrosopyrimidine with phenylacetonitrile?
(a) Sulfamerazine
(b) Alprazolam
(c) Triamterene
(d) Trimethoprim

30. Reaction of 3-chloro-N-phenylbenzeneamine with sulphur followed by alkylation with 3-o-dimethylaminopropyl chloride in the presence of sodium amide yields
(a) Alprazolam
(b) Sulfamerazine
(c) Chloropromazine
(d) Ketoconazole

31. Which of the following is an inhibitor of xanthene oxidase enzyme and prevent the synthesis of the uric acid and is useful in treatment of gout?
(a) Allopurinol
(b) Albuterol
(c) Pyrimethamine
(d) Dimercaprol

32. Tolmetin-glycine prodrug is an example for
(a) Bipartite
(b) Tripartite
(c) Mutual
(d) Bioprecursor

33. Bambuterol is the prodrug of this drug used to treat asthma, by converting its phenolic groups to Bis-dimethylcarbamate which otherwise undergoes rapid pre-systemic metabolism.
(a) Terbutaline
(b) Salbutamol
(c) Albuterol
(d) Levalbuterol

34. Which of the following is an irreversible enzyme inhibitor type?
(a) Competitive inhibitor
(b) Non competitive inhibitor
(c) uncompetitive inhibitor
(d) Suicide inhibitor

35. The peptide-based protease inhibitor Ritonavir is an example for
(a) Competitive inhibitor
(b) Non competitive inhibitor
(c) uncompetitive inhibitor
(d) Suicide inhibitor

36. Which of the following is an example for thioamide bioisosteric replacement Cyanoimino group?
(a) Metiamide and cimetidine
(b) Cholesterol and diazacholesterol
(c) Procainamide and procaine
(d) Uracil and 5-Fluorouracil

37. Which of the following drugs is not considered as fragmented analog of a lead molecule?
(a) Levorphanol
(b) Metazocine
(c) Meperidine
(d) Codeine

38. Which among the following antitubercular drugs, the (S,S)-(+)-enantiomer is used to treat tuberculosis while the (R,R)- (?)enantiomer is known to cause blindness.
(a) Isoniazid
(b) Ethambutol
(c) Rifampin
(d) Ethionamide

39. While designing the covalently binding enzyme inhibitors, this is the only common amino acid that has an electrophilic side chain and it also can be modified with suitable nucleophilic agents.
(a) Serine
(b) Threonine
(c) Tyrosine
(d) Arginine

40. Which of the following is an example for rationally designated mechanism-based inactivator drug?
(a) Lisinopril
(b) Vigabatrin
(c) Sulfanilamide
(d) Cimetidine

41. The antidepressant drug tranylcypromine acts by inhibiting the enzyme
(a) Xanthene oxidase
(b) MAO
(c) ACE
(d) GAB A transaminase

42. Which of the following drugs does not inhibit HMG-CoA reductase enzyme?
(a) Rosuvastatin
(b) Lovastatin
(c) Atorvastatin
(d) Losartan

43. Identify the drug-receptor interaction theory that states “even in the absence of drugs, a receptor is in a state of dynamic equilibrium between an activated form (Ro), which is responsible for the biological response, and an inactive form (To)”
(a) Occupation theory
(b) Induced fit theory
(c) Activation-Aggregation Theory
(d) Macromolecular Perturbation Theory

44. Which of the following anticancer drugs inhibits topoisomerase -II and is useful in the treatment of smalcell lung cancer non-Hodgkin’s lymphomal
(a) Etoposide
(b) 5-Fluorouracil
(c) Busulfan
(d) Methotrexate

45. Inhibitors of this enzyme are used as diuretics and in the therapy of glaucoma
(a) Mono Amine Oxidase
(b) Xanthene oxidase
(c) GABA transaminase
(d) Carbonic anhydrase

46. Which is the correct order of increasing wave number of the stretching vibrations of – (1) C-H (aldehyde), (2) N-H (alcohol), (3) C=O (ester), and (4) C?Ξ C (alkyne)?
(a) (4) < (3) < (2) < (1)
(b) (3) < (4) < (2) < (1)
(c) (3) < (4) < (1) < (2)
(d) (4) < (3) < (1) < (2)

47. Lycopene ( λmax = 469 nm) present in tomatoes absorbs which among the following range of visible light?
(a) Red
(b) Green
(c) Orange
(d) Blue

48. How many signals does the compound 3,3-Dimethyl butanal have in 1H NMR and 13C NMR spectra?
(a) five 1H signals and six 13C signals
(b) five 1H signals and four 13C signals
(c) three 1H signals and six 13C signals
(d) three 1H signals and four 13C signals

49. Which hydrogen of 1-Bromo-2-pentene shows the largest chemical shift (downfield) in its PMR spectrum?
(a) the H on C-1
(b) the H on either C-2 or C-3
(c) the H on C-4
(d) the H on C-5

50. The compound fentanyl is an analogue of-
(a) Phenyl piperidine
(b) Benzmorphan
(c) Propionanilide
(d) Morphinan