Cht Hoc C

ch3 HoC C

Condensation carbonium ion Geranyl or farnesyl pyrophosphate

FIGURE 2-14 (A) Conversion of mevalonic acid (51) into the intermediate 3-phosphomevaIonic acid 5-pyrophosphate (53), which is then decarboxylated to yield the nucleophilic 3-isopentenyl pyrophosphate

(1). Structure 1 is then isomerized into equivalent amounts of the electrophilic dimethylallyl pyrophosphate

(2). (B) Proposed mechanism for the key "head-to-tail" joining of the nucleophilic isopentenyl pyrophosphate to the allylic electrophilic "acceptor," which may be either dimethylallyl pyrophosphate (2) or geranyl pyrophosphate (53A). An encircled P indicates phosphate. (C) Pathway of reactions leading from isopentenyl pyrophosphate + dimethylallyl pyrophosphate to squalene (56). A key reaction is the "nose-to-nose" reaction of trans, fnms-farnesyl pyrophosphate (54) to yield presqualene pyrophosphate (55), which, after reduction by NADPH, produces squalene (56).

2. Steroid Hormones

trans-Geranyl pyrophosphate (53A)

trans-trans-Farnesyl pyrophosphate (54)

Presqualene pyrophosphate (55) NADPH + H+
Cure Tennis Elbow Without Surgery

Cure Tennis Elbow Without Surgery

Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.

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