Recent Developments in Non‐Mercurial Diuretics

Abstract

carbonium character. However, conjagation of the carbonyl group with the developing double bond should, in terms of the E 2 mechanism, provide a strong driving force. This should be especially powerful in elimination from XX because conjugation of -zwith -CO-would be established in the transition state. Moreover, these reactions conform to the trans-stereoelectronic pattern characteristic of E 2 reactions [60,61]. [60] H. B. ilther and T. Reichstein, Helv. Chim. Acta 26, 492 (1943); E. Seebeck and T . Reichstein, ibid. 26, 536 (1943). [61] N.

Stability and Degradation Pathways of N-Nitroso-Hydrochlorothiazide and the Corresponding Aryl Diazonium Ion

“…Preparation of 6-Chloro-4-nitroso-3,4-dihydro-2H-benzo-[e] [1,2,4]thiadiazine-7-sulfonamide 1,1-Dioxide (2). To a mixture of HCT 1 (300 mg, 1.00 mmol) and acetic acid (15 mL), sodium nitrite (487 mg, 7.05 mmol) was added at 25 °C.…”

“…Preparation of 6-Chloro-2H-benzo[e] [1,2,3,4]thiatriazine-7-sulfonamide 1,1-Dioxide (4). To a mixture of 6-chloro-4nitroso-3,4-dihydro-2H-benzo[e] [1,2,4]thiadiazine-7-sulfonamide 1,1-dioxide (NO-HCT 2; 2.60 g, 7.96 mmol), 50 mL of 10 mmol of Na 2 HPO 4 buffer, and 50 mL of acetonitrile, 1 M NaOH was added until pH 8 (1.5 mL). The obtained mixture was stirred at room temperature overnight.…”

“…Thus, it should be susceptible to N-nitrosation. Indeed, literature reports already highlight the preparation of Nnitroso-hydrochlorothiazide (2, 6-chloro-4-nitroso-3,4-dihydro-2H-benzo[e] [1,2,4]thiadiazine-7-sulfonamide 1,1-dioxide, NO-HCT, Scheme 1); 37,38 however, its reactivity was not explored in a broader context. In this report, we demonstrate that NO-HCT 2 is unstable in aqueous conditions at pH 1 to 8 and readily decomposes to several degradation products among which formaldehyde, aminobenzenesulfonic acid (3, 2-amino-4chloro-5-sulfamoylbenzenesulfonic acid, ABSA, Scheme 1), thiatriazine (4, 6-chloro-2H-benzo[e] [1,2,3,4]thiatriazine-7sulfonamide 1,1-dioxide, Scheme 1), and HCT 1 are the predominant ones.…”

Iridium‐Catalyzed ortho‐C−H Amidation of Benzenesulfonamides with Sulfonyl Azides

“…Specifically, 2‐aminobenzenesulfonamides act as a key precursor for the synthesis of benzothiadiazine 1,1‐dioxides . Classic methods for the synthesis of 2‐aminobenzenesulfonamides include sequential chlorosulfonylation of aromatic amine and ammonolysis with chlorosulfonic acid and the reaction of aromatic amine with chlorosulfonyl isocyanate followed by cyclization of the resulting chlorosulfonylureas with Lewis acids . Although these methods are efficient and reliable, they still suffer from several disadvantages such as harsh reaction conditions, moisture sensitivity, narrow scope of substrates, and isomer formation.…”

“…Notably, amidation does not take place when AgSbF 6 is used as silver salt (Table 1, entry 7). In additon, only moderate yields were obtained by employing AgOTf and AgTFA as silver salts(Table 1, entries8,9). Remarkably, the Ag 2 CO 3 showed excellent activity and gave 92% yield (Table 1, entry 10).…”