Page 23 - FPGEE Medicinal and Organic Chemistry Q&A Book

Krisman

ulbar neuritis, occurring in association with 256. (c) Dapsone or 4,4’-diaminodiphenylsulfone
ethambutol therapy may be characterized by one or 4,4’-Sufonyldianiline is an pharmacological
or more of the following events: decreased medication most commonly used in combination
with rifampicin and clofazimine as multidrug
visual acuity, scotoma, color blindness, and/or
therapy (MDT) for the treatment of Mycobacterium
visual defect. These events have also been re-
leprae infections (leprosy).
ported in the absence of a diagnosis of optic or
retrobulbar neuritis. Patients should be advised
O
to report promptly to their physician any change
of visual acuity. NH 2 S NH 2
O
253. (c) The compound shown in the structure
4,4'-Diaminodiphenylsulfone
is ethionamide (Trecator). The IUPAC name for
(Dapsone)
this compound is 2-ethylpyridine-4-
carbothioamide. It is antibacterial agent
257. (b) Cisplatin (Platinol) is organometallic
indicated for the treatment of tuberculosis.
neoplastic agent. It is used for the treatment of
metastatic testicular, ovarian and advanced
254. (c) Para-aminosalicylic acid is used as sec-
bladder cancer. Severe nausea and vomiting are
ond-line agent for the treatment of tuberculo-
reported with Cisplatin. Use of antiemetic agent
sis. It is thought to act as an antimetabolite in-
is required prior to cisplatin therapy.
terfering with the incorporation of p-aminoben-
Myelosuppression and ototoxicity, including ir-
zoic acid into folic acid. When coadministered
reversible hearing loss, is also reported with the
with INH (Isoniazid), para-aminosalicylic acid
therapy.
(PAS) is found to reduce the acetylation of INH,
itself being the substrate for acetylation, thus
258. (d) Cis-diamminedichloridoplatinum or
increasing the plasma level of INH.
Cisplatin or Platinol is highly nephrotoxic in
nature. It should be carefully prescribed with
255. (c) Phenazine, also called dibenzopyrazine,
other nephrotoxic agents such as
is a dibenzo annulated pyrazine and the parent
cyclophosphamide, ifosfamide and streptomy-
substance of many dyestuffs, such as the
cin.
eurhodines, toluylene red, indulines and safra-
nines. Being a phenazine derivative water-
259. (b) To protect patients against cisplatin-
insoluble dark-red dye, it leads to pigmentation
induced nephrotoxicity, patients should be hy-
of the skin and discoloration of tears, sweat,
drated with chloride containing solution prior
sputum and urine.
to therapy. Use of saline or mannitol diuretics
N is also recommended to promote continuous
excretion of the drug and its water soluble
metabolite. Cisplatin is very strongly bound to
N
plasma protein, and therefore dialysis cannot
phenazine or dibenzopyrazine
rescue patients from cisplatin induced toxicity.
Clofazimine (Lamprene) is used in combina-
260. (c) Sodium thiosulfate is used to minimize
tion with rifampicin and dapsone as multidrug
cisplatin -induced bladder and kidney toxicity.
therapy (MDT) for the treatment of leprosy.
The drug accumulates in renal tubules where it
neutralizes active drugs in the kidney. The serum

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