Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved. We evaluated the antihypertensive properties of 4-Tertbuthyl-2,6-bis(thiomorpholine-4-ilmethyl)phenol (TBTIF). Spontaneously hypertensive rats were treated with TBTIF or captopril (both at 1 mgkg-1d-1 intramuscularly for 4 days), and their blood pressure (BP) was assessed. In some experiments, concentration response curves to angiotensin I or angiotensin II were generated in rat aortic rings and in the absence or presence of Ang-(1-7), NG-monomethyl L-Arginine, or both; additionally, the angiotensin-converting enzyme (ACE) and ACE2 mRNA levels were quantified in the aortic rings using reverse transcription- polymerase chain reaction. TBTIF diminished BP and reduced angiotensin I-or angiotensin II-induced vasoconstriction. The presence of Ang-(1-7) induced a greater reduction in vasoconstriction, and this effect was reversed by L-NG-monomethyl arginine. Moreover, TBTIF decreased the mRNA of ACE and increased the mRNA of ACE2. In conclusion, TBTIF diminished rat BP through nitric oxide-dependent and nitric oxide-independent mechanisms. In contrast to captopril, TBTIF exhibits better antihypertensive properties through mechanisms that involve ACE2.