Recent advances in strategies of green synthesis of 1,3-oxazines- a brief review

1,3‐Oxazine as a Promising Scaffold for the Development of Biologically Active Lead Molecules

“… [20] Moreover, green organic synthesis is being preferred over multistep methodology due to less waste generation and sustainable process. Compared to the MCR, green synthesis involves single step product formation leading to efficient library generation via simple variation of starting material to generate the diversity [16] . In this section we describe the synthesis of Minimycin C and 5‐methyl‐3H‐1,3‐oxazine‐2,6‐dione, naturally occurring compounds containing 1,3‐oxazine moiety.…”

“…Compared to the MCR, green synthesis involves single step product formation leading to efficient library generation via simple variation of starting material to generate the diversity. [16] In this section we describe the synthesis of Minimycin C and 5-methyl-3H-1,3-oxazine-2,6dione, naturally occurring compounds containing 1,3-oxazine moiety. Synthesis of reported derivatives containing 1,3-oxazine ring is discussed in next section along with their reported biological activities.…”

“…Moreover, several methods for 1,3‐oxazine derivatives synthesis have been reported [13–15] . The green synthesis represents an advantage over other methods because of its simplicity, reproducibility, affordability and stable products with no requirement of harmful chemicals, energy, pressure or high temperature [16] . The ring chain tautomerism has been reported as a characteristic phenomenon of N ‐unsubstituted tetrahydro‐1,3‐oxazine, dihydro‐1,3‐ and 1,3‐benzoxazine derivatives and is involved not only in structural characterization but also in determining their dual‐type reactivity [17] .…”

“…[13][14][15] The green synthesis represents an advantage over other methods because of its simplicity, reproducibility, affordability and stable products with no requirement of harmful chemicals, energy, pressure or high temperature. [16] The ring chain tautomerism has been reported as a characteristic phenomenon of Nunsubstituted tetrahydro-1,3-oxazine, dihydro-1,3-and 1,3benzoxazine derivatives and is involved not only in structural characterization but also in determining their dual-type reactivity. [17] Because of the interesting chemistry and wide variety of applications as therapeutic agents, 1,3-oxazines are of considerable interest to the researchers.…”

Antiproliferative Activity of (−)‐Isopulegol‐based 1,3‐Oxazine, 1,3‐Thiazine and 2,4‐Diaminopyrimidine Derivatives

“…[4] In addition, many synthetic compounds have 3-amino-1,2-diol moieties in their backbones, including the antitumor agent aminocyclopentitol pactamycin, the proteasome inhibitor TMC-95 A, the immunosuppressant antibiotic myriocin, riboflavin (vitamin B2) and the hydrogenase coenzyme F420. [5] Besides being of pharmacological interest, 3amino-1,2-diols have proven to be excellent building blocks for the synthesis of various heterocyclic compounds such as 1,3oxazine, [6,7] 1,3-thiazine [8] and pyrimidines. [9] Pyrimidines belong to an important class of heterocyclic structures found in many synthetic and naturally occurring products with a remarkable spectrum of biological activities.…”