Abstract:
Isoquinolinones (I-oxo-l ,2-dihydroisoquinoline) are a class of fused heterocycles that are
of increasing interest in synthetic and pharmaceutical chemistry. A convenient and facile
method for the synthesis of 1,2,3,4-tetrahydro-l-oxoisoquinoline-3-carboxylic acid by.
palladium-catalyzed reaction of N-substituted-2-iodobenzamide with acrylic ester IS
reported. N-(Alky) Aryl-2-iodobenzamides 10-15, when stirred with acrylate 16-21 111
presence ofbis (triphenyl phosphine) palladium (II) chloride in DMF and triethylamine at
80 °C for 24 h gave N-substituted-3-alkylisoindolin- I-one acetate 22-29 which af1()rded
N-substituted-l,2,3,4-tetrahydro-l-oxoisoquinoline-3-carboxylic acid 30-35 on base/acid
catalyst hydrolysis.
~I
C_NHR
II
10 - 15 0
2 / H,C = CHCN
~ ~ - 20 CH2-COORI
H,C = (: - CORI / H,C = CHCHO ~
16-19 21
(PPhJ),PdCI2, E-tJN •. N-R + 0 rQl NHR
DMF, N, aIm I ~
80 °c, 24 hrs. 22 _ 29 0 36.-d 0 .
rArJCOOH 0yN-R
o
30 - 35
(i) NaOH (1.5 eq), MeOH
Reflux 1.5 - 2 hrs.
or
(ii) 2N H2S04, 80 "C, 1.5 - 21m.
In Vitro antimicrobial activity of 3-substituted isoindolinone acetate and isoquinolinone-
3-carboxylic acid were evaluated. The compounds demonstrated mild growth inhihilion
against antibiotic-susceptihle standard and clinically isolated strains or Gram positive and
Gram-negative bacteria as well as human fungal pathogens.
