... To the best of our knowledge, PYR was determined with either MEC or CYC using different analytical methods, such as spectrophotometry (Arayne, Sultana, Siddiqui, Zuberi, & Mirza, 2007;El-Gindy, 2003;El-Gindy, Emara, & Mostafa, 2004;Habib, Abdelwhab, Abdelrahman, & Ali, 2016;Sharma, Sharma, Saxena, & Talwar, 1989;Shinde, Sayyed, Chaudhari, Chaware, & Biyani, 2016), HPLC (Al-Jallad, Al-Kurdi, Badwan, & Jaber, 1999; Arayne, Sultana, & Siddiqui, 2008;El-Gindy, Emara, & Mostafa, 2004;Li & Lu, 2005;Mao & Carr, 2001;Nawaz, 2013;Sher et al., 2014), and chemometric/UV methods (El-Gindy, 2003;El-Gindy, Emara, & Mostafa, 2004). Moreover, MEC was determined using LC stability-indicating assay method (LC-SIAM) in tablets (Peraman, Manikala, Kondreddy, & Yiragamreddy, 2015). ...