Topical dinitrochlorobenzene (DNCB) for alopecia areata: Revisited

Acid Hydrazides, Potent Reagents for Synthesis of Oxygen-, Nitrogen-, and/or Sulfur-Containing Heterocyclic Rings

“…213 Hydrazinolysis of 1,3,4-oxadiazole 111 moiety 154 yielded 48% of 4-amino-4H-1,2,4-triazole-3-thiol structure 309 (Scheme 85). 104 A series of 1,2,4-triazole derivatives prepared following a similar procedure was reported by Mohan, 214 Dhiman, 215 Mostafa, 125 Demirbas, 208,210 Kumar,216 Prasad, 217 Seleim, 218 and Vainilavicius et al 219 Reaction of terephthalic acid hydrazide 237 with phenyl/ benzyl isothiocyanate and phenyl isocyanate in DMF in the presence of sodium hydride gave the nonisolable intermediates Refluxing hydrazide 49 in acetic acid initially produced 1,3,4thiadiazole derivative 314, which underwent ring opening under the prevailing reaction conditions and then ring closing of the intermediate 315 to afford the 1,2,4-triazole thione 316 in 86% yield (Scheme 87). 67 Three-component condensation reaction of acid hydrazides, S-methyl isothioamide hydroiodides 317, and ammonium acetate on the surface of silica gel under microwave irradiation gave the corresponding 3,5-disubstituted-1,2,4-triazoles 318 in 66−91% yields (Scheme 88).…”

Alopecia areata: An update

“…Mohan et al reported acceptable terminal hair growth in 36% of their patients using DNCB and suggested a relook at DNCB therapy. [69] Diphenyl-cyclo-propenone (DPCP) and squaric acid dibutyl ester (SADBE) are other contact sensitizers used in AA. The efficacy of the both agents is almost same 50-60% with a range of 9-87%.…”

“…[68] ANTHRALIN ANTHRALIN Anthralin is an irritant, and it's mechanism of action in AA is unknown. It is effective because of its Corticosteroids [5,29,[63][64][65] Corticosteroids [63][64][65][78][79][80][81][82][83][84][85][86][87] Cyclosporine A [91] Calcineurin inhibitors [97,98] Minoxidil [66][67][68] Sulfasalazine [88,89] Methotrexate [92] Biologicals [99,100] Anthralin [5,65] PUVA [90] Azathioprine [93] NBUVB [101] Immunotherapy [69][70][71][72] Capsaicin [94] Phototherapy [73,74] Topical bexarotene 1% gel [95] Prostaglandin analogues [75][76][77] Camoufl age [96] immunosuppressive and anti-inflammatory properties by generating free radicals. [5] It...…”

Vitiligo after Diphencyprone for Alopecia Areata

“…Topical immunotherapy is used to treat alopecia areata and recalcitrant warts since the 1970s [ 1 ]. Daman, Rosenber, and Drake in 1978, demonstrated the effectiveness of dinitrochlorobenzene (DNCB) in 2 patients with Alopecia Areata [ 2 ], and new studies have been conducted in the attempt to establish the therapeutic potential of this agent [ 3 – 5 ]. However, some authors questioned the safety of this chemical, suggesting a possible carcinogenic potential [ 6 – 8 ].…”