CLASSIFICATION

Prostaglandins are classified mainly into two groups shown in Table 4.5:

Prostanoids are further subdivided into three groups:

Structure of prostaglandins:

Figure 4.8 Structure and Biosynthetic Pathway of Prostaglandins

Table 4.5 Structure of Prostaglandin

Prostaglandin	Substituent Group	Structure
PGA	Double bond C₁₀—C₁₁ keto group C₉
PGB	Double bond C₈—C₁₂ keto group C₉
PGC	Double bond C₁₁—C₁₂ keto group C₉
PGD	—OH group at C₉ keto group at C₁₁
PGE	Keto group at C₉ OH group at C₁₁
PGF	OH group at C₉ and C₁₁
PGG	Two O₂ atoms present at C₉ C₁₁ are bonded; hydroperoxide group at C₁₅
PGH	Ring the same as in PGG; —OH group at C₁₅
PGI	Attachment of O₂ between C₆ and C₉, forming another 5-carbon ring